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46 articles trouvés pour ce sujet.
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.
A rectangular prism with rounded corners 2018-04-25
Jackie pose la question :
Rectangular prism that is 40 by 20 with rounded corners with a radius of 2.5.

What would the surface area be?

Penny Nom lui répond.
A square peg in a round hole 2017-05-29
bill pose la question :
bill wants to put a 2 foot square peg into a round hole What must be the circumference of the hole?
Penny Nom lui répond.
Why does 10x10x10 give 1,000.0000000000001? 2017-04-12
Randolph pose la question :
Hi, On your calculator I found that a box 10 by 10 by 10 inches has a volume of 1,000.0000000000001 cubic inches. Can you explain the numeral 1 thirteen places past the decimal? Thanks, Randy
Penny Nom lui répond.
Can you construct a regular 21-gon? 2016-03-08
Peter pose la question :
hi, i know that if i use a compass to draw a circle, i can use the same setting to mark 6 intervals along the circle circumference, how would i go about marking out 21 equally spaced points around the circumference?

if there an online calculator i can us, or some other interesting trick?



Robert Dawson lui répond.
Prove the earth is round 2016-01-30
Kevin pose la question :
Working on a project for a science fair.
To prove the earth is round without the ability to get way above the surface.
How could we set up and experiment to see the curve.
My thought is using a telescope at the beach?
Form what we see so far the curve is 8 inches per mile?
So thought is set up a telescope and a target 1 mile away?

Robert Dawson and Chris Fisher lui répond.
The surface area of a round bar 2015-06-06
chirag pose la question :
Please tell me the formula for finding round bar surface in square inches/ mm
Penny Nom lui répond.
A string wrapped around three circles 2013-10-19
Jim pose la question :
A recent puzzle ' find the length of a string around 3 touching 1 meter diameter circles ' gave this answer : the string touches 120° (or pi/3 meters) of each circle. Then 3(1+pi/3) = 3+pi meters is the required length. I do not see how it was determined that the string touches 120° or pi/3 meters?
Please explain . Thank-you , Jim

Penny Nom lui répond.
6 golfers in threesomes over 7 rounds 2013-09-24
David pose la question :
I have 6 golfers, (2 threesomes) who will be playing 7 rounds of golf. What is the best way to pair the 6 players so they play with as many different players over the 7 rounds?
Victoria West lui répond.
8 golfers, 3 rounds 2013-04-15
justin pose la question :
I have 8 golfers going on a trip. We have 3 rounds to play. We would like to play with everyone (with or against.) Is this possible? If so could you send me the formula please and thank you!
Robert Dawson lui répond.
Milling round stock to square stock 2012-12-17
Bryan pose la question :
Question from Bryan:
I want to know what the smallest diameter round is that will make a 3-1/4" square? Is there a formula for that? I am milling round stock into square.
Thank you.

Harley Weston lui répond.
The volume of a round tube 2012-02-07
I.C pose la question :
I need to find out how long a 10" round tube needs to be in order for there to be .95 cubic feet of air space
Harley Weston lui répond.
Rounding 2011-12-14
seth pose la question :
A decimal number rounded changed to 23.7 after it was rounded. Give a decimal number that is less than 23.7 and another that is greater than 23.7 that each round to 23.7. Explain to what place each number was rounded.
Penny Nom lui répond.
16 golfers and 8 rounds 2011-05-26
Gerry pose la question :
16 golfers and 8 rounds. To have each player play with as many others as possible.
Victoria West lui répond.
The nearest one and a half and the nearest inch 2011-02-02
Miranda pose la question :
REASON:sarah gave the same answer when asked to round 4 seven eighth inches to the nearest one and a half and the nearest inch. explain why sarah is correct?
Penny Nom lui répond.
A rectangle with rounded corners 2010-10-21
Connie pose la question :
How do you find surface area if the rectangle is 100ft. by 200ft. with quarter circles in the corners with a radius of 20ft. ?
Penny Nom lui répond.
An 18ft round pool 2010-07-19
christine pose la question :
will an 18ft round pool fit on a 12x16 ft rectangular cement slab?
Tyler Wood lui répond.
3 equidistant points on a circle 2010-06-21
Brian pose la question :
We have to line up 3 pins on a lifting bridle to be 120 degrees apart from each other to connect into a lifting assembly.
I know pi*d. I know straight lines connecting these points to each other will result in an equilateral triangle. How does one find these points without using a protractor? There must be a formula (formulae) to work this out mathematically.
r = 10.5 inches
pi*d = 65.9736
3 segments( arcs) = 21.9912 which is the distance along the circumference that the points are from each other.

Penny Nom lui répond.
15 golfers 3 rounds fivesomes 2009-12-23
Dewey pose la question :
I have 15 golfers playing 3 rounds of golf. We will be playing in fivesomes. Any formula that has everyone playing with a different person each round?

Thank you. Dewey

Robert Dawson lui répond.
Greatest Number in Rounding Off 2009-06-25
paucath pose la question :
what is the greatest number that can be rounded of to 4000
Janice Cotcher lui répond.
A 4 digit number 2009-04-12
kaylin pose la question :
When a 4 digit rounded to the nearest thousand,it rounds up to 3000. the hundred digit is less than 6. the digits in the ten and ones place add to a sum of 8 and they are the same . what is the number
Robert Dawson and Penny Nom lui répond.
A three digit number 2009-01-20
marcha pose la question :
when this three digit number is rounded to the nearest ten, the sum of its digits is 16 the hundreds digit of this number is 8 and the ones digit is 5, what is the number?
Robert Dawson lui répond.
Compatible numbers 2008-10-02
jeff pose la question :
what exactly are compatible numbers, math problem is:
Estimate the total weight of 2 boxes that weigh 9.4 pounds and 62,6 pounds using rounding and compatible numbers. Which estimate is closer to the actual weight and why?

Harley Weston lui répond.
Rectangular cards on a round table 2008-06-11
Susan pose la question :
How many 4" X 3.5" wide escort cards will fit on a 48" diameter table. These are for my daughters wedding. I have already added the extra spacing between the cards into the size of the cards.Thanks for your help
Janice Cotcher and Harley Weston lui répond.
Rounding 2008-05-09
wendell pose la question :
write a three digit number that when rounded to the nearest ten and the nearest hundred, the answers are the same
Penny Nom lui répond.
Rounding 2007-11-05
Charles pose la question :
I have been asked to explain why rounding to 3 decimal places has become the adopted industry standard in mathematics for showing measurement calculations. I understand that it makes sense to round financial calculations to 2 d.p. because then it's rounded to the nearest penny (or cent) but why would the standard in measurement be 3?
Stephen La Rocque lui répond.
Dirt in a sloped round hole 2007-08-03
Ken pose la question :
How much dirt do I need to fill a ground hole 20 ft in dia. with a sloping floor that has a ht. of 5" on one side and 12" on the other side?
Stephen La Rocque lui répond.
The size of a lot 2007-06-13
Larry pose la question :
This is driving me crazy, I know i learned this in college but that was so many years ago haha. I am trying to determine how many acres my property is. Unfortunately everywhere i look is like another language to me when seeing these formulas. My property is square shaped so starting from one side and just working around the dimensions are: 114 feet x 95.88 feet x 100 feet x 91.91 feet.
Penny Nom lui répond.
Percentage increase and decrease 2007-06-13
Anna pose la question :
I just want to if the following formula is used for the computation of a PERCENTAGE DECREASE:

Old Value - New Value/ Old Value x 100%

My immediate superior is under the impression that the said formula works ONLY for the computation of a percentage INCREASE. He believes that the formula for a percentage DECREASE:

Old Value - New Value/ NEW Value x 100%

On this score, I want to know the correct formula for the computation of percentage decrease. Thank you so much.

Penny Nom lui répond.
A 5 digit key 2007-05-31
Michael pose la question :
I have a 5 digit key pad lock on my truck. I want to print out all of the combinations to try. pad one=0 pad two =1 pad three=2 pad four=3 pad five =4. can you help me find and print all combinations?
Harley Weston lui répond.
Water tank volume 2007-05-29
Cecelia pose la question :
Stephen La Rocque lui répond.
Rounding off 2007-04-15
deepak pose la question :
find the smallest and the greatest numbers which when rounded off to the nearest thousand, become 6000.
Stephen La Rocque lui répond.
Angular speed 2006-10-04
Jack pose la question :
A horse on a merry-go-round is 7m from the center and travels at a speed of 10km/h. What is its angular speed?
Stephen La Rocque lui répond.
Estimating products by rounding 2006-09-24
Ann pose la question :
my son is in the fifth grade and they are doing estimate products rounding both factors, he knows how to round off a decimal, but he is having a problem doing a decimal and a whole number for example 5.96x3=? He knows the 5.96 round off to 6. but what does the 3 round off to?
Penny Nom lui répond.
An aircraft going from city A to city B 2006-05-10
Preston pose la question :
An aircraft going from city A to city B on a bearing of S69 degrees East is traveling at a speed of 430 mph. The wind is blowing out of the north to south at a speed of 25 mph. Find the ground speed and the plane's true bearing.
Stephen La Rocque lui répond.
Round to the nearest tenth 2006-05-06
Lisa pose la question :
how to round a decimal fraction to the nearest tenth
Penny Nom lui répond.
How do you round off 89,100? 2006-04-19
Jeannie pose la question :
My home work says to round each number to the place of the underlined digit. It has 89,100. The underlined number is 9. What do I do?
Stephen La Rocque lui répond.
Find the ground speed and the planes true heading. 2006-02-05
Jimmie pose la question :
An aircraft going from city A to city B on a bearing of S69E (degrees) is traveling at a speed of 430 mph. The wind is blowing out of the north to south at a speed of 25 mph. Find the ground speed and the planes true heading.
Penny Nom lui répond.
how do i round up 9.6 to the nears ones 2005-08-09
Carlos pose la question :
how do i round up 9.6 to the nears ones
Penny Nom lui répond.
Round to hundredths 2002-11-19
Brittany pose la question :
Can u tell me how to do a problem like this:

35 divded by 4.8= Round to hundreths.

Penny Nom lui répond.
Rounding 27.27 2002-11-03
A parent pose la question :
If you have a problem 27.27 and you need to round to the first 7 the answer would be 27

Would 27.0 be acceptable as well or is it completely wrong.

Penny Nom lui répond.
Multiplication of fractions 2001-01-08
Angela pose la question :

1. represent multiplication of fractions via an area model

2. describe why, not just how, to round decimals

Penny Nom lui répond.
Rounding 2000-09-14
MaryAnn pose la question :
How many whole numbers rounded to the hundreds place, round to 400? Can you also explain why?
Penny Nom lui répond.
Rounding 2000-04-15
Tawana Brown pose la question :
I was uncertain as to whether a number such as 85.25 rounding to the nearest tenth would be 85.3 or 85.2. I thought I had heard somewhere that if 5 is the last number that you don't round up. But I have also heard that anything 5 and above you do round up. It's been awhile since I've done rounding, so I need a refresher course.
Walter Whiteley and Harley Weston lui répond.
Spreading a rumor 1999-09-13
Bornstar14 pose la question :
There is someone who wants to spread a rumor within 7 days to 250,000,000 people. he wants to know how many people he should tell on the first day (assuming the rumor is passed by everyone who was told to the same amount of people) so that everyone knows on the 7th day. What I did is the 7th root of 250,000,000. this answer is not possible unless rounded. is it okay for the number to be approximate?
Penny Nom lui répond.
Intersecting Lines. 1998-02-10
Erik Heppler pose la question :
My typewriter frequently makes mistakes. Suppose I gave you the following system of equations to solve:

35.26X + 14.95Y = 28.35
187.3X + 79.43Y = 83.29

When I looked back, I realized that I meant to use 14.96 as the "Y" coefficient in the first equation instead of 14.95. Solving the system using 14.95 and then solving another system using 14.96 with all other values the same both times results in the intersection points (1776, -4186) and (-770, 1816) respectively.
How can that be?
Penny nom lui répond.




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