.
. centre de ressources dilemmes et doutes le visage humain de mathématiques Qui sommes-nous Problème de mois activités de promotion babillard
Centrale des maths - centraledesmaths.uregina.ca
Dilemmes & doutes
« D & D »
. .
topic card  

Sujet:

sit

liste de
sujets
. .
nouvelle recherche

175 articles trouvés pour ce sujet.
 
Page
1/1
Filling holes with stone dust 2020-07-30
Zach pose la question :
I’m looking for amount of stone dust needed for thirteen holes with a 3ft depth and 12in diameter with a 4x4 post. I would need the measurement in KG.
Harley Weston lui répond.
Running in opposite directions around a circular track 2020-05-11
Alessandra pose la question :
2. Alan and Brian are two runners. Alan runs at 6.6 m/s and Brian runs at 8.4 m/s. They start from the same place on a circular 400 m track and run in opposite directions round and round the track.
(a) How far has Brian run when they pass each other for the first time?
(b) After they pass each other for the second time, how much further does Brian need to run in order to complete two laps (800 m)?

Penny Nom lui répond.
Four consecutive positive integers 2019-03-12
Nabila pose la question :
The product of four consecutive positive integers in 24024
What is their sum?

Penny Nom lui répond.
Running around a circular track in opposite directions 2019-02-24
carmi pose la question :
how many times will lita and rose pass each other in 15 minutes if lita and rose start jogging on a 110 meters circular track. they begin at the same point but in opposite direction. lita at 8/3 meters per second and rose at 7/3 meters per second.
Penny Nom lui répond.
Composition of functions 2019-02-24
Joshua pose la question :
Let g(x)=(x)^(2)+x-1 Find such a function f such that (fog)(x)=(x)^(4)+2(x)^(3)-3(x)^(2)-4x+6
p lui répond.
The domain of f(g(x)) 2018-06-18
Joshua pose la question :
What are the restrictions of the domain of f(g(x))?
Penny Nom lui répond.
The inverse square law 2018-06-05
Amy pose la question :

Question about inverse square law ;

Hi, I'm trying to understand some nuances about this law and
have been reading about it a lot online and trying out some homework
for personal interest (hobby ) - not school related.

I understand that the simple formula is ; 1/d^2

I was wondering about what appears to be an oddity to me, that
I came across when I was working with a test example I found at this
link ;

http://www.softschools.com/formulas/physics/inverse_square_law_formula/82/

The problem that caught my interest was this one on that page ;

"1) If a bright flashlight has a light intensity of 15.0 candela at a distance 1.00 m from the lens, what is the intensity of the flashlight 100.0 m from the lens?"

So I have a few different questions about this, but the most important
one is, what does it mean if we replace the "1" in ; 1/d^2 with a different value such as a ratio in the form of a decimal value, so instead we have something like this ;

0.75/d^2

???

Does this ratio represent a curve then?

I am thinking that the "1" in the normal formula represents a straight line

Some of the links I was researching ;

http://wisptools.net/book.php?c=3&s=2

http://www.softschools.com/formulas/physics/inverse_square_law_formula/82/

https://www.nde-ed.org/GeneralResources/Formula/RTFormula/InverseSquare/InverseSquareLaw.htm


Penny Nom lui répond.
mg to ml 2018-05-17
Carolynne pose la question :
I need to convert 12 mg to ml
density is 12.5mg/5ml
I can give dose of 1mg per pound . My dropper is in ml.
How much in ml can I give

Penny Nom lui répond.
Positive and negative values of a function 2018-01-30
Grayson pose la question :
f(x)=x^6-x^4
Interval: ( negative infinity, negative one )
Test Value: negative two
Function Value f(x): positive forty eight
Interval: ( negative one, zero )
Test Value: negative one
Function Value f(x): zero
Interval: ( zero, positive one )
Test Value: positive one
Function Value f(x): zero
Interval: ( positive one, positive infinity )
Test Value: positive two
Function Value f(x): positive forty eight

What is the sign of f(x) for each Interval?

Penny Nom lui répond.
The mass of a length of tree trunk 2017-11-13
SM pose la question :
What is the mass of a length of 1m of trunk a tree trunk of uniform cross section of area 0.5 sq.m is made of wood of relative density 0.8?
Penny Nom lui répond.
f(x)=-x^2-6x find f(x-2) 2017-10-27
Kenneth pose la question :
f(x)=-x^2-6x find f(x-2)
Penny Nom lui répond.
The composition of a function with itself 2016-07-17
Mel pose la question :
If f(1 + 3x) = 1 * x, solve f(f(x))
Penny Nom lui répond.
Covering a site with 6 inches of rock 2016-04-26
Carla pose la question :
if a pump house that measures 20'x16' sits in the middle of a site that is 50'x60' and you apply crushed rock to the site at depth of 6", how many yards will you need to haul?
Penny Nom lui répond.
Filling a hole with 14 tons of rock 2016-04-08
Barry pose la question :
If I had 14 tons of inch and one half sized aggregate rock, how large of a square or rectangular shaped hole would I need to hold that amount?
Penny Nom lui répond.
Travelling in opposite directions 2015-12-06
Roselyn pose la question :
Jenny and Mark commute to work, travelling in opposite directions. Jenny leaves the house at 8 AM, and averages 35 kph. Mark leaves at 8:15 AM, and averages 40 kph.At what time will they be 40 kilometers apart?
Penny Nom lui répond.
The weight of a steel block 2015-04-04
Mark pose la question :
the weight of a steel cube 37 inches X 28 inches X 7 inches
Penny Nom lui répond.
Two consecutive positive integers 2015-03-01
meha pose la question :
Find two consecutive positive integers , sum of whose squares is 365.
Penny Nom lui répond.
A stone is dropped in a lake 2015-02-14
Wendy pose la question :

Hi, I have problems solving this problem. We didn't exactly go over these kind of problems and the book doesn't have an example either. Thank you for your help!

A stone is dropped in a lake, creating a circular ripple that travels outward at a speed of 80 cm/s.
(a) Find a function g that models the radius as a function of time t.

g(t) =

(b) Find a function f that models the area of the circle as a function of the radius r.

f(r) =

(c) Find f compose g.
f compose g =


Penny Nom lui répond.
Mutually prime composite numbers 2015-01-09
nivedita pose la question :
Two composite number that is mutually prime?
Penny Nom lui répond.
The density of sea sand 2014-11-02
Lenny pose la question :
Hi There,

I need to find out the the density of sea sand to convert one metric ton to cubic meter as I am submitting for a tender which is in cubic meter but the requirement is in metric ton. I searched through the web site but no density of sea sand is given though there is specific Gravity of dry sand is available. I was given a density of 1.6 to work with. If that is true am I right to say that 1 cubic meter of sea sand is equivalent to 1.6 metric ton? Please help as I am getting confused with what I am able to find out on the web.
Thanks much in advance
Rgds
Lenny

Penny Nom lui répond.
Revisiting 8 golfers in two foursomes 2014-08-19
steve pose la question :

I noticed you had an answer on how can you put 8 golfers in even foursomes over 7 games so that everyone plays with everyone equally. However the formula showed the following sequence that was used but did not go past the second day. Can you change the 0s and 1s into the numbers 1 to 8 instead. Here is what you have written:
Day 0 : (0, 0, 0, 0, 1, 1, 1, 1)
Day 1 : (0, 0, 1, 1, 0, 0, 1, 1)
Day 2 : (0, 1, 0, 1, 0, 1, 0, 1)
Day 3 : (0, 1, 1, 0, 1, 0, 0, 1)
Day 4 : (0, 0, 1, 1, 1, 1, 0, 0)
Day 5 : (0, 1, 0, 1, 1, 0, 1, 0)
Day 6 : (0, 1, 1, 0, 0, 1, 1, 0)

Thank you so much for your anticipated help.

Steve


Harley Weston lui répond.
A small solid silver pyramid 2014-06-13
Jenesis pose la question :
For Awards Night at Baddeck High School, the math club is designing small solid silver pyramids.The base of the pyramids will be a 2 in by 2 in square. The pyramids should not weigh more than 2.5 pounds. One cubic foot of silver weighs 655 pounds. What is the maximum height of the pyramids?
Penny Nom lui répond.
The weight of salt in a basket 2014-05-17
Sumit pose la question :
I want to determine how many kg of salt or XYZ thing can be filled in a basket
Length = 4.5"
Breadth = 5"
Height = 6"

Even its formulae

is kg quantity can be different for semi solid thing

Penny Nom lui répond.
A slab of wet clay 2014-04-12
Karen pose la question :
How many square feet ( at 1/4 inch thickness) are in 100 lbs. of wet clay?
Penny Nom lui répond.
A silver figurine 2013-05-03
Renee pose la question :
I have a silver figurine, the density of silver is 10.5g/cm3. if the figurine weighed 149 g. to determine the volume, he dropped it into a cylindrical glas of water. the diameter of the glass is 6 cm and the figurine was pure silver, by how much should the water level in the glass rise?
Penny Nom lui répond.
The continuity of f(x,y)=ln(x^2+y^2) 2013-02-17
anu pose la question :
the question says we have to find the points in the plane where the function is continuous: f(x,y)=ln(x^2+y^2) . here we aren't given a particular point (x,y) where we have to check a function's continuity. what is to be done if we have to check continuity over the whole domain of the function? please help .
Harley Weston lui répond.
A relation on a collection of sets 2013-02-04
raji pose la question :
suppose R be a non empty relation on a collection of sets defined by ARB if and only if A intersection B is nullset.then.....the correct answer is R is symmetric and not transitive...my doubt is how it is symmetric
Penny Nom lui répond.
The weight of a pipe full of water 2013-01-16
joe pose la question :
how do you figure out the weight of a pipe full of water
Harley Weston lui répond.
Transposition error 2012-12-03
Carol pose la question :
What is the correct term for when a child writes 61 instead of 16, or 83 for 38--when they switch the place values of a number?
Chris Fisher lui répond.
A function problem 2012-11-18
nahla pose la question :
f: IN --> IN
n --> f(n)
for every n that belongs the IN : fof(x) = 4n - 3
and for every n that belongs to IN f(2^n) = 2^(n+1) -1

Calculate f(993)

Penny Nom lui répond.
A proof by contraposition 2012-10-19
Rahul pose la question :
I am not able to understand the following,
To prove that if for all e>0, |x|0, then |x|>=e. I understand the approach very well but I do not understand why if |x|=e then |x|>=e. If it is so then why not |x|= Thanks in advance!'
Rahul.

Penny Nom lui répond.
Composition of functions and one to one 2012-10-17
Ariana pose la question :
If f o g are one to one function,does it follow that g is one to one? Give reasons for your answers
Penny Nom lui répond.
The position of an aircraft relative to the airport 2012-06-08
Dennis pose la question :
"Air traffic controllers usually describe the position of an aircraft relative to the airport by altitude, horizontal distance, and bearing.  Suppose an aircraft is at altitude 500m, distance 15km, and bearing 35 degrees east of north.  What are the x,y, and z components (in meters) of the position vector. The x-axis is east, the y-axis is north and the z-axis is vertical.
Penny Nom lui répond.
A uniform probability density function 2012-03-26
Noeline pose la question :
The label on a bottle of liquid detergent shows contents to be 12 ounces per bottle. The production operation fills the bottle uniformly according to the following probability density function:
f(x) = 8 for 11.975 ≤ x ≤12.10
and
f(x) = 0 elsewhere

a. What is the probability that a bottle will be filled with 12.02 or more ounces?
b. What is the probability that a bottle will be filled between 12 and 12.05 ounces?
c. Quality control accepts production that is within .002 ounces of number of ounces shown on the container label. What is the probability that a bottle of this liquid detergent will fail to meet the quality control standard?

Penny Nom lui répond.
One acre of dirt 6 inches deep 2012-01-11
Cameron pose la question :
Ok what im wanting to know is how many pounds of dirt are in 80 acres of land that is 6 inches deep? My friend and I are stumped on this question
Penny Nom lui répond.
Limits and composition 2011-12-30
Rahul pose la question :
I want to know about limit proofs of composite functions. Like limit of log of a function equals log of limit of the function
Penny Nom lui répond.
The weight of 36 inch steel pipe 2011-12-22
Keith pose la question :
What is the weight of 36 inch steel pipe 3/4 wall per foot in lbs.
Penny Nom lui répond.
The LCM of 6,15 and x is 90 2011-10-30
Richie pose la question :
Hi there,
There are 2 parts to the question.
#1. Factorise 90. This is easy, 90=2x3x3x5

#2
LCM of 6,15 and x is 90. What are possible values of x if x is odd?

From #1, since 90=6x15, how can this be used to work out possible values of x?

Thanks in advance, Richie

Penny Nom lui répond.
Composition of functions 2011-09-05
Jenna pose la question :
Let f(x)=x^2-1 and g(x)=1-2x. Find the indicated values.
1. f(g(1)) and g(f(1))

Thanks,
Jenna

Penny Nom lui répond.
The mass of a metal box 2011-03-11
Pamela pose la question :
A metal block has the dimensions of 3.16 inches wide, 2.15 inches high, 4.98 inches long. What is the volume of the block in cm^3? What is the block's mass if the metal has a density of 5.89g/cm^3.
Robert Dawson lui répond.
The weight of a tank 2011-01-11
tom pose la question :
A tank, open at the top is made up of thin sheet iron 1in. thick. The internal dimensions of the tank are 4 ft. 8in. in long ;3 ft. 6 in.in wide ;4ft 4 in. in deep Find the weight of the tank when empty, and find the weight when full of salt water. (Salt water weighs 64 lbs. per cu. ft., and iron is 7.2 times as heavy as salt water)
Harley Weston lui répond.
How many gallons of water will it take to fill a classroom? 2010-12-01
deena pose la question :
How many gallons of water will it take to fill a classroom that is 26 feet long by 19 feet wide and 9 feet high? How many tons of water will that be?
Stephen La Rocque lui répond.
The weight of some dirt 2010-11-03
Maggie pose la question :
I am wanting to know how many tons of dirt we r going to need to fill a basement. The measurements we r going with r 15ftx15ftx8ft.
Penny Nom lui répond.
Disposing of some concrete 2010-08-12
Kathy pose la question :
We are needing to dispose of concrete that we are tearing out of our backyard and I need to figure the dimensions and weight. I figured we have approx. 419 sq ft of concrete at 4" thick. Could you tell me the how much that comes to in cubic ft, cubic yards and weight. So I can get some estimates on pricing to haul off and dispose of. thank you
Harley Weston and Tyler Wood lui répond.
70 cubic meters of mulch 2010-07-30
zsuzsi pose la question :
i have 70 cubic meters of mulch to move and an 8 tonne truck to use how much tonnage is to 1 square meter so that i can work out how many trips i need to make
Penny Nom lui répond.
The tonnage of some gravel 2010-07-22
Gregory pose la question :
i have a road that is 8 miles long 20 feet wide and 4 inches deep what is the tonnage for gravel i would need
Penny Nom lui répond.
The test for some disease is 99% accurate 2010-02-24
baaba pose la question :
Assume that the test for some disease is 99% accurate. If somebody tests positive for that disease, is there a 99% chance that they have the disease?
Chris Fisher lui répond.
4-digit positive numbers 2010-02-15
marjon pose la question :
Find the sum of all the 4-digit positive numbers with no zero digit.
Penny Nom lui répond.
The intervals where the function is positive and negative 2010-01-10
Ron pose la question :
Hello

I'm trying to find out the intervals where the function is positive and negative. It's for a polynomial function y= -(x+2)^2 (x-2) and y= (x+1)(x+4)(x-3)

I have tried the right and left side of each x-intercepts, but I still don't understand the results

thank you for your help

Penny Nom lui répond.
Finding Density Given Volumetric Thermal Expansion Coefficient 2009-12-26
florence pose la question :
Hi- Please help me to apply the formula for this problem. The coefficient of volumetric for gold is 4.20 X 10^-5 C degrees. The density of gold is 19,300 kg/m^3 at 0.9 C degrees. What is the density of gold at 1050 degrees C. Could you please explain how to get the solution of 18,500 kg/m^3 Thank you for your help Florence
Janice Cotcher lui répond.
A number base that's not a positive integer 2009-12-11
Nick pose la question :
Is it possible for a number to have a base that's not a positive integer? Base 1 gives a result that's meaningless but possible. I have no concept of a base 0, a negative base, or a fractional base, never mind any other base. I think there isn't any base that's not a positive integer, but, knowing that math keeps jumping ahead and sometimes has inventions before anyone knows how to exploit them, I think I'd better ask.

Thank you.

Nick

Robert Dawson and Claude Tardif lui répond.
Density of dirt and gravel 2009-10-26
ken pose la question :
if digging a load of dirt and gravel in mining how many yards of material to the ton thanks
Penny Nom lui répond.
Sawdust 2009-09-29
joel pose la question :
What is the density of saw dust
Harley Weston lui répond.
Gravel in an aquarium 2009-08-09
Bev pose la question :
Hi...I worked this part out, but want to know how many kilograms of gravel I will need...thanks Bev

Cylinder shape.

A cylindrical shape that has a radius of 82 centimeters and a depth of 7 centimeters has a volume of: Volume

= 0.14787 cubic meters
= 147870 cubic centimeters
= 0.1934 cubic yards
= 5.2219 cubic feet
= 9023.5 cubic inches
= 39.063 U.S. gallons
= 147.87 liters
* calculations accurate to 5 decimal places of precision

Harley Weston lui répond.
Cubic meters of gravel in a 7 ton lorry 2009-06-21
Jackie pose la question :
I have to transport gravel in a 7 ton lorry and I know how many cubic meters of gravel I need, but I need to know how many cubic meters of gravel a 7 ton lorry can hold.
Thanks, Jackie

Penny Nom lui répond.
Percent increase from a negative number to a positive number 2009-04-21
Brian pose la question :
I have no problem calculating year over year net profits but am having trouble when it comes to a negative.
2007 Net Profit = -110,333.00
2008 Net Profit = 66,054.00

Brian

Harley Weston lui répond.
Comparing positive and negative fractions 2009-03-24
Christyrose pose la question :
Hello. I am a sixth grade math student and i need help on how to compare negative and positive fractions.

Here is is:
3/4 -2/3 7/10 -5/6

I'm not sure how to do the negative parts because i was absent for a couple days. Thank you!

Christyrose

Penny Nom lui répond.
The amount of material remaining on a reel 2009-03-04
James pose la question :
Question from james:

I am after a standard calculation so that after each usage of the Reel I can get the Remaining Quantity in kilos left on the roll

below is an example of roll

THICKNESS: 30 MICRON
REEL WIDTH: 7.5 CM
REEL DIAMETER: 76 CM
REEL WEIGHT: 7.13 KILOS

The core centre has a 9cm diameter, the weight of the roll is excluding the core , and after each use the diameter of the role is measured.

I am a factory supervisor working on project and need this calculation info for template.. Thanks James

Harley Weston lui répond.
Pressure at Given Depth 2009-02-22
Tamara pose la question :
A sea is 3km deep. The average density of sea water there is 1020 kg/m^3. What is the water pressure at the bottom?
Janice Cotcher lui répond.
The volume of a yogurt pot 2008-12-04
Robyn pose la question :
Okay, I know you have some answers on converting this already, but I can not convert the yoghurt pot I need yet into ml. Is there some way to explain this using the yoghurt as an example? The pot's 150g of lowfat strawberry yoghurt... would the 'low-fat' have an effect on this? I'm sorry if this is a bother for you to answer, I just don't seem to be able to get it... Have a nice day. - Robyn
Janice Cotcher and Penny Nom lui répond.
A product of positive and negative numbers 2008-10-03
kaylou pose la question :
Suppose you were given 13 numbers and asked to find their product. Seven of the numbers were positive, and the rest were negative. Would your product be positive or negative? Why?
Penny Nom lui répond.
The weight of a concrete cylinder 2008-09-18
Curtis pose la question :
I am trying to calculate the weight of a concrete cylinder. The diameter is 56" and the thickness or depth is 24". Can anyone help me? If possible I would like to see the formula as to how the answer was derived. Thank you
Harley Weston lui répond.
557 mL of benzaldehyde 2008-08-28
Kara pose la question :
Calculate the mass of 557 mL of benzaldehyde. The density of benzaldehyde is 1.04 g/mL.
Penny Nom lui répond.
Right Sided Limit of an Exponential Function 2008-07-29
joseph pose la question :
I am trying to find the limit as X approaches 0 from the positive side of x to the sin of x which look like this lim x^sinx x->0+
Harley Weston lui répond.
Three consecutive positive integers 2008-07-20
AC pose la question :
find three consecutive positive integers such that the product of the first and third, minus the second, is 1 more than 4 times the third
Penny Nom lui répond.
Neither prime nor composite 2008-07-08
saloni pose la question :
Give the counting number which is neither prime nor composite ?
Penny Nom lui répond.
Composition of two functions 2008-07-04
Kristian pose la question :
f(x)= the square of x add to 1 and g(x)=1/x

find: (f o g)x

Penny Nom lui répond.
The weight of concrete 2008-06-11
Daniel pose la question :
I need to calculate the weight of Concrete in a slab that measures 2' x 4' x 4" thick. I am pricing out a job and have two different size stones to work with, the second stone measures 2' x 2' x 4".
Harley Weston lui répond.
.5 cu ft of sand to lbs. 2008-05-25
rogersimmons pose la question :
needtocovert .5 cu ft. of sand into lbs.
Penny Nom lui répond.
Volume/weight of a salt shedweight 2008-05-21
James pose la question :
How do I find the volume/weight of a salt shed. I have a 3000 ton barn, I need a better way of finding how much salt to order as it gets used. I know how to calculate volume, how do i get tonnage from there??
Harley Weston lui répond.
The weight of a concrete column 2008-05-11
russell pose la question :
a cylindrical form is filled with a slow curing concrete. The base of the form is 10 ft in radius, and height is 25 ft. while the concrete hardens, gravity causes the density to vary from a density of 90 lbs/ft^3 at the bottom to a density of 50 lb/ft^3 at the top. Assume that the density varies linearly from the top to the bottom, and compute the total weight of the resulting concrete column
Harley Weston lui répond.
Converting metric density 2008-04-28
Hilary pose la question :
10g/100ml=?g/?l
52g/100ml=?g/?l
65g/100ml=?g/?l
100g/100ml=?g/?l
137g/100ml=?g/?l
0.15g/100ml=?g/?l

Penny Nom lui répond.
A 13 cubic foot cylinder filled with sand 2008-04-12
Thomas pose la question :
I have a 100 pound bag of sand. I need to know how much sand I will need to fill a 13 cubic foot cylinder
Harley Weston lui répond.
The weight of 1 litre of milk 2008-04-07
IMRAN pose la question :
WHAT WEIGHT IN KILOGRAMS DOES 1 LITRE OF MILK HAVE?
Penny Nom lui répond.
Composition of functions: feet, inches and yards 2008-04-05
Coya pose la question :
write a function f(x) that converts feet to inches.Now write a function g(x) that converts yards to feet. Explain what the composite function f(g(x)) means. Then evaluate f(g(x)) for x = 3,6, and 9.
Stephen La Rocque lui répond.
A car tire full of concrete 2008-03-27
robert pose la question :
I want to build a volleyball net support. I am using a car tire 24"odx16"id filled with concrete. how much will this weigh? thanks
Penny Nom lui répond.
A ton of carbon dioxide 2008-03-11
claire pose la question :
I want to know the size of a box if it contained a ton of Co2?
Stephen La Rocque lui répond.
Composition of functions 2008-03-07
sharon pose la question :
Find FoG(x)
F(x)= the square root of x-9
G(x)= x^2
and also find GoF and their domains

Penny Nom lui répond.
Why is the number 1 neither prime nor composite? 2008-02-07
ronni pose la question :
why is the number 1 neither prime nor composite?
Harley Weston lui répond.
Bubbles trapped in the volumetric pipet 2008-01-31
Nursing pose la question :
In determining the density of a liquid, a student left air bubbles trapped in the volumetric pipet. Did this give a density less than expected or greater than expected? Why?
Penny Nom lui répond.
The volume of a tank 2008-01-27
Fred pose la question :
A cubic tank holds 1,000 kilograms of water what are the dimensions of the tank in meters?
Harley Weston lui répond.
Converting mg's to cc's 2008-01-17
sandy pose la question :
i need to find out how to convert mg's to cc's i need to give 10 mg of liquid and 5 mg of liquid and i only have a dropper that measures cc's please help
Stephen La Rocque and Harley Weston lui répond.
Transformations and compositions 2007-11-29
mary pose la question :
Is there any possible relationship between composite functions and the concept of function transformations?
Harley Weston lui répond.
Density 2007-11-29
jessuca pose la question :
what is the density for 40g / 2 mL
Penny Nom lui répond.
I know it's heavy, but how heavy, per linear foot? 2007-11-19
Gary pose la question :
I am trying to find out the weight of a linear foot of a steel bar with the following measurements.
Thickness - 1.125"
Length - 120"
Height - 18"

Density of carbon steel - .2837
I know it's heavy, but how heavy, per linear foot?

Stephen La Rocque lui répond.
A mole of hydrogen peroxide 2007-11-11
John pose la question :
i need to get a mole of hydrogen peroxide, which i know is 34g, but i don't have a way to measure grams, so do you know how many mililiters i need to have 34g of hydrogen peroxide. Thanks for all the help
Stephen La Rocque lui répond.
How do i convert milliliters to grams for water and also for copper sulfate (CuSO4)? 2007-11-11
jenn pose la question :
how do i convert milliliters to grams for water and also for copper sulfate (CuSO4)?
Harley Weston lui répond.
Why is the number 1 neither prime nor composite? 2007-11-08
amarilis pose la question :
why is the number 1 neither prime nor composite?
Penny Nom lui répond.
Density 2007-10-30
Ali pose la question :
Would an object sink or float in pure water if it has a mass of 10g and a volume of 5 cubic centimeters? 314
Stephen La Rocque lui répond.
How many tons of asphalt are in 12 cubic yards? 2007-10-15
Matthew pose la question :
I want to know how many tons of asphalt are in 12 cubic yards?
Penny Nom lui répond.
Motion along a line 2007-10-02
Claudette pose la question :
If the position function of a particle is x(t) = sin^2(2t), find the distance that the particle travels from t = 0 to t = 2
Harley Weston lui répond.
A 3 ounce piece of gold 2007-09-24
Helen pose la question :
What would the volume (in mL) of a 3 ounce piece of gold be?
16oz= 1lb
1lb= 454oz.
first i converted 3oz to lbs and then to grams to get the mass. i got 85.125 g. now i don't know how to get the density to get to the volume.

Stephen La Rocque lui répond.
Volume, mass and density 2007-09-14
Nathan pose la question :
I have a sample of material that is 10cmx10cmx5cm and has a mass of 29 grams. How many grams would a sample of the same material that was 96cmx188cmx5cm be?
Penny Nom lui répond.
How much stone will be needed to fill the trench? 2007-09-14
Debbie pose la question :
A trench 100metres long 1ft wide*18inches deep with a 4inch pipe laid. How much stone will be needed to fill the trench.
How much weight in stone would I need to fill it?

Penny Nom and Victoria West lui répond.
Is it platinum or silver? 2007-09-14
Jordan pose la question :
In Chemistry we are doing a lot of problems that are much more math related than anything. One of my questions reads: A certain medallion has a mass of 55.64 g. When placed in 75.2 mL of water in a graduated cylinder, the water level rises and then reads 77.8 mL. Is the medallion made of platinum (D=21.4 g/mL) or silver (D= 10.5 g/mL)?
Penny Nom lui répond.
Composite angles 2007-09-13
Gilbert pose la question :
what is a composite angle? please help
Stephen La Rocque lui répond.
What was the water level in the cylinder? 2007-09-11
glen pose la question :
After a 5.63-g sample of Wood's metal has been added to the water in a 10-mL graduated cylinder, the new water level is 8.7mL. What was the water level in the cylinder before the sample was added?
Stephen la Rocque lui répond.
Grams of vodka 2007-07-10
Andrew pose la question :
milliliters to grams..vodka 80 proof?
Stephen La Rocque lui répond.
Derivative of a Function 2007-07-09
Bob pose la question :
What is the derivative of the function a sub n = [n/(n+1)]^n ?
Stephen La Rocque lui répond.
Tons of concrete 2007-07-03
Trey pose la question :
I have 300,000 square feet of concrete and want to know how to convert this to tons?
Harley Weston lui répond.
How do I convert milliliters(powder form) to grams? 2007-06-28
ed pose la question :
How do I convert milliliters(powder form) to grams
Harley Weston lui répond.
How many tons of sand? 2007-06-19
Richard pose la question :
I need to know how many tons of sand it would take to fill a container 20 feet long, 20 feet wide, and 6 inches deep. I am not sure of the makeup of the sand as far as dry, loose, wet, etc. If you could give me calculations of all the variants it would be appreciated.
Stephen La Rocque and Penny Nom lui répond.
The composition of functions 2007-06-14
Gilligan pose la question :
Question from Gilligan, a student:

Let f(x) = x^2, g(x) = 3x and h(x) = (sqrt{x}) + 1. Express each function as a composite of f, g and/or h.

(1) p(x) = 3(sqrt{x}) + 3

(2) Q(x) = (sqrt(sqrt{x}) + 1}) + 1

Penny Nom lui répond.
Composition functions 2007-06-12
Gilligan pose la question :
Find functions f and g so that f(g(x)) = H.
(1) H(x) = (1 + x^2)^(3/2)
(2) H(x) = int(x^2 + 1)
I don't know where to start.

Stephen La Rocque lui répond.
The number of grams of sulfuric acid 2007-05-31
cookie pose la question :
Hi,
Can you please let me know if I've done this correctly?

Calculate the number of grams of sulfuric acid in 0.500L of battery acid if the solution has a density of 1.28 g/mL and is 38.1% sulfuric acid by mass.

Stephen La Rocque lui répond.
How many tons of dirt is this? 2007-05-23
Deb pose la question :
I need to know how many tons of dirt(6 inches deep)would it take to cover 8 acres?
Stephen La Rocque lui répond.
Converting mass of sand to volume (a sand ceremony) 2007-05-21
Linda pose la question :
I'm getting married. We are having a sand ceremony. The empty bottle we are using holds 800ml. I have bags of colored sand. Each bag is 30g. There is 7 people participating in this ceremony. What I need to find out is how many grams of sand i need for 7 people to participate to fill this jar.
Penny Nom lui répond.
A ton of sawdust 2007-05-10
David pose la question :
I am trying to do a conversion. A tractor trailer is loaded with 165 cubic yards of sawdust (I do not know the actual weight). I knw the wholesale cost as $1,000 for this amount, but would like to convert this to find out what the equivalent cost for a metric ton would be.
Stephen La Rocque lui répond.
Probability of H.I.V. tests 2007-05-07
Danielle pose la question :
A medical test detects H.I.V. Among those who have H.I.V., the test will detect the disease with probability 0.95; among those who do NOT have H.I.V., the test will falsely claim that H.I.V. is present with probability 0.0125. Among those who take this test, 4% have H.I.V. The test is given to Lucille, and indicates that she has H.I.V. What is the probability that Lucille actually has H.I.V.?
Stephen La Rocque lui répond.
How many tons of sand is needed 2007-04-25
Jennifer pose la question :
How many tons of sand is needed to cover 350 cubic square feet?
Penny Nom lui répond.
How can I convert milliliters to grams? 2007-04-18
April pose la question :
What if I'm using cow's milk, how can I convert milliliters to grams?
Stephen La Rocque lui répond.
Yards of sand in a ton 2007-04-09
Teresa pose la question :
how many yards of sand are in a ton and how many yards of limestone does it take to make a ton
Penny Nom lui répond.
What is the intensity 5m below the surface? 2007-03-31
david pose la question :
I have this question which I am supposed to set it up and solve as a differential equation. I know how to solve the diffrential equation but I am having hard time understanding this question. Here is the question: The intensity of light in the ocean decreases the deeper you dive. In fact, the rate at which the intensity decreases is proportional to the current intensity. Setup the corresponding differential equation and solve for I(Y), the intensity I as a function of current intensity Y. If the light intensity 2m below the surface is 25% of the intensity at the surface, what is the intensity 5m below the surface. Can you please explain to me what does it mean by current intensity and how do I set this equation up. Thanks for the help.
Penny Nom lui répond.
Factoring a trinomial 2007-03-27
Kim pose la question :
Hi, could you please help me solve this.

3x(squared) +20x - 7

Leeanne Boehm lui répond.
Concrete sand 2007-03-08
david pose la question :
Can you tell me how much 4 cubic yards of concrete sand ways in tons? THANK YOU.
Stephen La Rocque lui répond.
Centimeters to cubic meters and grams to kilograms 2007-02-14
Colleen pose la question :
A box of balls measures 120cm by 20cm by 20cm and weighs 48 g.
One thousand boxes = x cubic meters and weighs x kilograms.
Also, one million boxes = x cubic metes and weighs x kilograms.
One billion boxes = x cubic meters and weighs x kilograms. Solve for x.

Stephen La Rocque lui répond.
Density 2007-02-09
Judy pose la question :
How do I calculate the mass in grams of 125mL of chloroform when d=1.49g/mL.
Stephen La Rocque lui répond.
The density of an irregular wooden block 2007-01-30
Carlos pose la question :
I'm trying to help my son but I don't really have too much knowledge about this topic. he is been asked to convert 10 milliliter to gram, I think that since 1 g = 1ml the answer will be 10 g also there is another question of how of the density of an irregular wooden block is affected if:
a) the center is hollow:
b) the block is not completely submerged when determining the volume.

Stephen La Rocque and Penny Nom lui répond.
Why zero is neither prime nor composite? 2007-01-17
Brenda pose la question :
Why zero is neither prime nor composite?
Penny Nom lui répond.
I want to convert milliliters into grams. 2006-12-14
Kenchotenzin pose la question :
I want to convert milliliters into grams.
Penny Nom lui répond.
What is the diameter of the planet? 2006-12-07
Niall pose la question :
In April 2005, scientists claimed to have captured light from an extrasolar planet orbiting a brown dwarf in the constellation Hydra some 230 light-years from Earth. The scientists believe the planet is about five times the mass of Jupiter.

Assume the planet has the same density as Jupiter. What is the diameter of the planet?

Stephen La Rocque lui répond.
solve; 2006-11-28
Monique pose la question :
solve; f(f(x)) = 2x + 4 ; if f(x) = 1
Penny Nom lui répond.
Composition of functions 2006-11-19
RJ pose la question :
Let f0(x) = 2/2-x and fn+1 = f0 o fn for n greater than or equal to 0. Find a formula for fn and prove it by mathematical induction. Recall that o represents function composition. i.e., (f o g)(x) = f(g(x)).
Stephen La Rocque lui répond.
Composition of functions 2006-11-18
Oryan pose la question :
Given f(x)=-2x^3 and g(x)-4x-5, find g(f(-1))
Stephen La Rocque lui répond.
Two problems involving density 2006-10-06
Patricia pose la question :

1. Nick has to ship 650,000 g of substance A to Singapore. The density of substance A is 3.23g/cm^3. If the delivery charge is 0.25 centavo per cm^3,how much does he need to pay?

2.Ann ordered 150 balloons for a birthday. Each balloon has a radius of 20cm. If the density of helium is 0.124g/cm^3,how many grams of helium is needed to meet the order?


Stephen La Rocque lui répond.
How much does 1300cc of liquid weigh? 2006-04-28
Debra pose la question :
How much does 1300cc of liquid weigh, and how is the formula equated?
Stephen La Rocque lui répond.
How much money can I borrow if I have $5 000 for a deposit? 2006-04-19
Chris pose la question :
I have a sum of cash that I want to use as a deposit ($ 5 000) and a lender will lend me 65% of the purchase price. How do I calculate the maximum value I can borrow?
Stephen La Rocque lui répond.
A proof by contraposition 2006-03-16
Eban pose la question :

1)by mathematical induction prove that 12 + 32 + 52 + ...... + (2k-1)2 = (1/3)k(2k-1)(2k+1) for all positive integers k.

2)show that the contrapositive of the following statement is true. if 1 + M7 is even, then M is odd.


Stephen La Rocque lui répond.
An account that earns 6% annually 2006-03-01
Christine pose la question :
How much do you have to deposit to an account that earns 6% annually if you want to earn $1200 on the account?
Stephen La Rocque lui répond.
Percentage increase in sound intensity 2006-01-29
David pose la question :
I am doing some emotion response mapping. Being a composer I know how to push the heart beat tempo by a % increase of BPM in my music. I want to know how to calculate an increase in intensity of sound. Now I have 60 decibels. I want an increase of intensity by a factor n% with out going over 156 decibels.
Penny Nom lui répond.
Composite triples 2006-01-24
Laeah pose la question :
question 1 Find the smallest integer n such that n+1, n+2,and n+3 are all composites.

question 2 If n = 5! +1, show that n+1, n+2, and n+3 are all composite.

question 3 Find the sequence of 1000 consecutive composite numbers.

Penny Nom lui répond.
I need to order sand for playgrounds 2006-01-18
Jody pose la question :
I need to order sand for playgrounds. I have their square footage and the various depths of sand needed for each, but sand comes in tons.

What is the formula for converting square footage and depth to tons (for example: 6 inches of sand needed for a 200sq ft area = how many tons?)

Penny Nom lui répond.
fog 2005-11-12
Janice pose la question :
I am having problem with the (fog) function

(fog) (x). Given f(x)= 2x2 ; g(x)= 3-4x

Penny Nom lui répond.
Whole numbers 2005-10-10
Kirk pose la question :
Can the sum of two or more whole numbers be less than any of those numbers?
Penny Nom lui répond.
Adding positive and negative numbers 2005-09-03
Billy pose la question :
46 + -24 =
-38 + -22 =
19 - 20 =

Penny Nom lui répond.
Spraying roses 2005-03-03
A student pose la question :
A litre and a half of water has 0.045 grams of herbicide added for spraying roses. How many grams of herbicide per litre is this?
Penny Nom lui répond.
A seating arrangement 2005-02-03
Kay pose la question :
If you have 5 married couples, how many arrangements can be made if they must sit across from each other?
Penny Nom lui répond.
Strategies for teaching operations with positive and negative decimal numbers 2005-02-02
Erin pose la question :
I am wondering if you can suggest any strategies for teaching operations with positive and negative decimal numbers that do not rely on rules that must be memorized?
Diane Hanson lui répond.
An isosceles triangle 2005-01-03
Abraham pose la question :
The question is,"Triangle ABC is not isosceles.Prove that if altitude BD were drawn, it would not bisect AC."My question is If an altitude is drawn wouldn\'t that mean automatically its isosceles because, In a triangle the sides opposite congruent angles(in this case the right angles)are congruent? What am I thinking wrong?
Harley Weston lui répond.
1/4 tsp salt = ??? grams 2004-11-16
Julie pose la question :
if i have 1/4 teaspoon of salt how many grams does that equal
Penny Nom lui répond.
Visitor wins or home wins 2004-09-29
Paavn and Laddi pose la question :
I have a math question i am stumped on for one of my classes. The question states that there are 14 baseball games with 2 possible outcomes for each game, visitor win or home win. How many different total combinations are possible from the 14 games?
Penny Nom lui répond.
Pizza for Jack? 2004-09-16
Grace pose la question :
Jack is playing pool with Jim for $1 a game. He has only $2 and decides to play until he goes broke or has $5, at which point he will quit and go out for a pizza with Jim(Dutch treat). Jack knows from past experience that he beats Jim 60% of the time. What is the probability that Jack will get to eat pizza? Hints: Let A be the 6x6 matrix defined by A=[aij], where aij is the probability that Jack will have $(i-1)after one game is he starts with $(j-1). For example, a23 - .40 since there is a 40% probability that Jack will end up with $1 after a game is he starts the game with $2 (If Jack wins 605 of the time, he must lose 40% of the time). Also, for example, a52 = 0 since there is no way jack can have $4 after one game if he had $1 at the beginning of the game. Since Jack will stop if he goes broke or accumulates $5, a11 and a66 are both 1.

Let x0 = [0 0 1 0 0 0 ] transposed, which we interpret as saying that initially Jack has $2 with a probability 1. Then Ax0 will represent the porbability of each amount of money, $0-$5, after one game. What is the probability that Jack will be able to eat pizza by computing Akx0 for large k and finding a limiting value.

Penny Nom lui répond.
Limits and composite functions 2004-08-07
Sue pose la question :
I have two questions, one about a limit and the other about a composite function. If you could help me, I'd really appreciate it.

1. Find the limit:

lim[x->0] (x*csc(x))

I converted csc(x) to cos(x)/sin(x), but I didn't know what to do after that.

2. f(g(x)) = ln(x^2 + 4), f(x) = ln(x^2) and g(x) > 0 for all real x, find g(x):

I'm having trouble with this one because x^2 + 4 isn't a perfect square.

--Sue

Penny Nom lui répond.
The sum of some positive integers 2004-06-07
A student pose la question :
Find the sum of all positive integers not greater than 10000 that are divisible by neither 3 nor 7.
Penny Nom lui répond.
A probability density function 2004-04-14
A student pose la question :
The label on a bottle of liquid detergent shows contents to be 12 ounces per bottle. The production operation fills the bottle uniformly according to the following probability density function:

f(x) = 8 for 11.975 <= x <= 12.10
and
f(x) = 0 elsewhere

a. What is the probability that a bottle will be filled with 12.02 or more ounces? b. What is the probability that a bottle will be filled between 12 and 12.05 ounces? c. Quality control accepts production that is within .002 ounces of number of ounces shown on the container label. What is the probability that a bottle of this liquid detergent will fail to meet the quality control standard?

Penny Nom lui répond.
A snowball melts 2003-12-11
Adam pose la question :
A spherical snowball has diameter 10cm and density 0.75g/cm3. It is placed in a cylindrical can with diameer 12cm. After the snow melts it turns to water with density 1.0g/cm3. What will be the depth of the water in the can (to 1 decimal place)?
Penny Nom lui répond.
A fish tank 2003-11-26
Bill pose la question :
How do I work out the volume and weight of water in a fish tank that is 36in x 14in x 12in?
Penny Nom lui répond.
If 1 is neither prime nor composite... 2003-11-19
Joshua pose la question :
if 1 is neither prime nor composite...what is it called?
Claude Tardif and Penny Nom lui répond.
If 1 is neither prime nor composite... 2003-11-19
Joshua pose la question :
if 1 is neither prime nor composite...what is it called?
Claude Tardif and Penny Nom lui répond.
Making a square 2003-09-07
A student pose la question :
if I am given any number (say 80 for example), how may I determine the smallest whole number integer which when multipled by it will yield a square number ? In other words if I express this as: 80Ý*ÝnÝ=ÝsquareÝnumber, what is the least value of n which will yield a square.
Penny Nom lui répond.
Positive, negative and zero 2003-09-04
Brian pose la question :
Can the Value of zero be positive or can it be negative or can it be both.
Penny Nom lui répond.
Density 2003-02-19
Rob pose la question :
What is the formula for converting cubic feet to pounds? (with any substance)
Penny Nom lui répond.
Three consecutive positive intergers 2003-02-09
Yew pose la question :
Prove that when we multiply any consecutive positive intergers, the result is always divisible by 6.

ex. (7)(8)(9) = 504 = 6 (84)

Penny Nom lui répond.
Composites, primes, factors and common factors 2002-11-20
Connie pose la question :
My son can't remember what a composite number is, what a prime number is and the explaination of factors and common factors. Help!
Penny Nom lui répond.
n +1, n+2, n+3, and n+4 are all composite 2002-04-09
Jonathan pose la question :
Find the small integer n such that n +1, n+2, n+3, and n+4 are all composite
Penny Nom lui répond.
Composition of functions 2002-04-06
Yvonne pose la question :
In our new text book, the following question occurs: State the domain and range of g(f(x))given that f(x) = -x2 - 4 and g(x) = sqrt(x)

The range of f(x), x<=-4, is the domain of g(x). BUT, there is no solution in the Real numbers for g(f(x))= sqrt(-x2 - 4).

In the solutions it says that this is not a function and therefore does not have a domain or range. Is it a relation? Is it anything?


Claude Tardif lui répond.
Baseball and sit ups 2002-01-31
A student pose la question :
A baseball team won 8 more games than it lost. If it played 56 games, how many games did it win?

On the first day of practice, Paul did 3 sit ups. On the second day he did 5, and on the the third day he did 8, and on the fourth day he did 12. If this pattern continued, how many sit-ups did ihe do on the sixth day of practice?


Penny Nom lui répond.
Composition of functions 2001-12-16
Paula pose la question :
  1. if f(x)= 3x-1 and g(x)= 1/2x + 3 find fog(2)

  2. find the values of x for which tanx=0

Penny Nom lui répond.
Negative times negative is positive 2001-10-26
Mary pose la question :
I have a question about adding and multiplying positive and negative numbers. When we add two negative numbers the answer is negative BUT when we multiply two negative numbers the answer is positive. I don't understand. Why?
Penny Nom lui répond.
Marginal Propensity to Consume 2001-05-09
Esther pose la question :
The derivative of the national consumption function C = f(y) is called the ____________________.
Judi McDonald lui répond.
Neither prime nor composite 2001-05-08
Marc pose la question :
what 2 numbers are neither prime nor combitative?
Penny Nom lui répond.
A sequence of even terms 2001-04-29
A student pose la question :
A sequence c is defined recursively as follows:

c0 = 2
c1 = 4
c2 = 6

ck= 5ck-3 for all integers

Prove that cn is even for all integers.


Leeanne Boehm and Penny Nom lui répond.
An order relation 2001-02-12
Amy pose la question :
What is an order relation?
Claude Tardif lui répond.
The city transit system 2001-01-07
Jacky pose la question :
The city transit system carries an average of 9450 bus riders a day, for a fare of $1.75 each. The city wants to reduce car pollution by increasing ridership and to maximize the transit system's revenue at the same time. A survey indicates that the number of riders will increase by 150 for every $0.05 decrease in fare.
Harley Weston lui répond.
False Positives 2000-10-29
James pose la question :
A rare disease infected 1 in 1000 people in the population. A test for the disease is accurate 99% of the time when given to an infected person and also when given to a heathy person.
  1. Fill out a two-tier tree diagram and find the probability of the false positive(i.e the conditional probabily of being healty even when tested postive by the test) Comment on the result?

  2. ...

Penny Nom lui répond.
LOG(LN(x)) = 1 2000-07-28
An algebra student pose la question :
LET F(x)=LOG X AND G(x)= LN X. SOLVE (f *G)(x)= 1
SHOW COMPOSITION AND USE DEFINITION OF LOGS.

Harley Weston lui répond.
(mn + m + n)/(m^2 + n^2) = 1 2000-07-24
William pose la question :
Find all pair of positive integers m and n such that mn + m + n divides m2 + n2 = 1.
Peny Nom lui répond.
Natural numbers 2000-04-12
Sara pose la question :
What is a natural number???
Penny Nom lui répond.
Mass of the earth 2000-02-21
Terry Broughton pose la question :
My name is terry i am 15 my question is how much does our planet earth weigh ?
Chris Fisher and Harley Weston lui répond.
Whole numbers 1999-12-02
Patty pose la question :
I'm in a 5th grade class, please explaine what whole numbers are.....
Penny Nom lui répond.
Who is right 1999-09-04
rf, k, p and uncle a pose la question :
Good morning. Could you please, help us resolve and by the way, confirm "who is right"... regarding the solution of this problem: - a piece of metal is 6 in. wide by 2 in. in height and weights 500 pounds... - what is the weight of a piece made of same metal, 5 in. wide by 1 3/4 in in height? Could you please supply the "formula".

Regards, rf, k, p and uncle a.
Penny Nom lui répond.

Is zero positive? 1999-09-03
Shah pose la question :
Is zero a positive integer?
Penny Nom lui répond.
Division by a negative 1999-08-19
Sangeeta B. pose la question :
56/-8
Penny Nom lui répond.
Composite Numbers 1998-10-07
Greg Murphy pose la question :
What type of composite number has an odd number of factors?
Harley Weston lui répond.
How do you find out if a number is a composite or prime? 1996-09-16
Trish Feenstra pose la question :
Hi my name is Trish Feenstra. In grade 8. How do you find out if a number is a composite or prime if it is big like 37 529? Reply soon got a test on Friday the 13th
Denis Hanson lui répond.
 
Page
1/1

 

 


Centrale des maths reçoit une aide financière de l’Université de Regina et de The Pacific Institute for the Mathematical Sciences.

CMS
.

 

accueil centre de ressources accueil Société mathématique du Canada l'Université de Regina PIMS