.
. 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:

sum

liste de
sujets
. .
nouvelle recherche

113 articles trouvés pour ce sujet.
 
Page
1/1
Three numbers have a sum of 45 2020-05-06
Jayden pose la question :
Three numbers have a sum of 45. The greatest of the 3 numbers is 2 greater than the least number. What are the numbers? *
Penny Nom lui répond.
Sigma notation 2019-12-04
Kenneth pose la question :

What would be used for the top and bottom indices for the sigma sign in my example shown below?
If the amounts were 1 + 2 + 3, the top index would be 3 and the bottom would be i = 1, but if the amounts are 1 + 2 + 4, or 1 + 0.05 + 1/3, what would the indices be since these amounts are in an uneven pattern.

I thank you for your reply and explanation


Harley Weston lui répond.
The sum of the ages of Ruth and her mother is 77 years. 2019-11-06
Lydia pose la question :
The sum of the ages of Ruth and her mother is 77 years. The difference in their ages is 27 years. How old is each?
Penny Nom lui répond.
How many numbers from the set have the sum of its digits equal to 2? 2019-10-24
Marcel pose la question :
Hello. My question is the following: Given the set {1,2...........10exp2019}, how many numbers from the set have the sum of its digits equal to 2?
I got some of them : 2 20 200 2000 20000 .......2. 10exp2018 11 110 1100 11000 110000....101 1010 10100 101000 1010000....10011 10010 100100 1001000 1010000.....10001 100010 1000100 10001000,,,,,,100001 1000010 10000100....... My problem is that I have difficulty in finding a strategy to obtain the exact quantity of numbers.
Please help me, thanks

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.
A quadratic equation problem 2019-02-26
Em pose la question :
One root of the equation 2x^2 + bx - 24 = 0 is -8. What are the possible values of b and the other root?
Penny Nom lui répond.
The sum and difference of two numbers 2018-08-30
Saranya pose la question :
Hi,

The question is to find the numbers from sum and difference.
The Sum = 14 and the difference = 2

I found in this web site some useful answers. but my kid is going second grade only. She don't know how to do a division or multiplication.
So can you please explain on how to find the answer using only the Addition and Subtraction.

Thanks in advance.

Penny Nom lui répond.
The sum and difference of two numbers 2018-03-13
samima pose la question :
Two numbers have a difference of 0.85 and the sum 1.What are the numbers?
Penny Nom lui répond.
The sum and difference of two numbers 2018-01-25
Ali pose la question :

Hello,
I was looking at the original question that was posted and answered by
your team:
http://mathcentral.uregina.ca/QQ/database/QQ.09.07/s/donna1.html

I used the 7 and 4 as example and not looking for 39 per original
question:

A=7
B=4

7+ 4 =11 and 7-4 = 3

We end up with 11 +3 = 14

A= 14/2 give use 7

B = how do you solve for B or 4 with out knowing anything about 3 or any other numbers ?

Thank you
Ali


Penny Nom lui répond.
The sum and difference of two numbers 2017-03-20
Olivia pose la question :
The sum of two numbers is 87 and their difference is 29. What are the two numbers
Penny Nom lui répond.
A road trip word problem 2016-04-10
Marc pose la question :
While on a road trip I imagined this random word problem. Suppose I start a trip of 75 miles. My initial speed is 75 miles per hour. After every mile traveled I decrease my speed by one mile per hour. After the first mile I decrease my speed to 74 miles per hour and so on for each subsequent mile traveled. How long will it take to complete the 75 mile journey?
Penny Nom lui répond.
The integral of a sum 2016-03-10
Rahul pose la question :
How to solve definite integral of a sum. The specific problem is as follows,
Integral of ( 1+ sum of x^k, k=1 to k=n), x=0 to x=b *dx.
The answer is b + sum of b^(k)/k, k=2, to k=n+1. I understand only the integral of first term. But integral of the sum I do not understand at all.

Penny Nom lui répond.
The sum of the angles of a triangle 2016-02-24
Sophia pose la question :
Does every triangle add up to 180 degrees? (Such as a unique triangle)
Penny Nom lui répond.
Fractions of two quantities 2016-01-22
Melody pose la question :
Kate ate 1/4 of her orange. Ben ate 2/4 of his banana. Did Kate and Ben eat 3/4 of theit fruit? Explain.
Penny Nom lui répond.
The sum of two repeating decimals 2015-10-22
Kaitlin pose la question :
Here is the question I am struggling with:

Is the sum of two repeating decimals always repeating decimal? Explain your answer and give an example.

I answered this question thinking that no you cannot but only when adding 0.9 repeating, but my professor said this was incorrect.

Thanks for the help!
-Kaitlin

Penny Nom lui répond.
1 + 2 + 3 + ... + (2n - 1) 2015-01-01
Brian pose la question :
Hi Maths Central
My wife presented me with a query which may have a simple answer, but one that I can’t deduce or explain.

Take the string of numbers, n=1,2,3,4,5…
It seems that n(2n-1) = Sum((1…..(2n-1))
e.g. for n=5, both 5 x 9 and Sum(1….9) equal 45, and so on for other values of n.

Could you please provide an explanation? Does it have an underlying reason and a name?

Look forward to your response.
Brian

Penny Nom lui répond.
Two quadratic polynomials 2014-10-28
khushboo pose la question :
The zeroes of a quadratic polynomial x^2+ax+b are 'c' and 'd' and the zeroes of a quadratic polynomial x^2+cx+d=0 are 'a' and 'b'. find the numerical value of a+b+c+d where a, b, c and d are non zero integers.
Penny Nom lui répond.
The sum of two numbers is 52 2014-09-01
Blake pose la question :
The sum of two numbers is 52 and the difference is 10. What are the numbers? i used to be real good at this stuff?
Penny Nom lui répond.
A price increase and a consumption decrease 2014-08-16
sujan pose la question :
If the price of petrol increases by 25% and Rajesh intends to spend only 15% more on petrol then by how much % should he reduce the quantity of petrol he buys?
Penny Nom lui répond.
The combination of 6 numbers from 1 to 355 that gives us 360 2014-05-29
Ion pose la question :
Hi,
My name is Ion and I am trying to find the number of combinations of 6 numbers (angles) that would sum to 360 (degrees).

Thank you!

Robert Dawson lui répond.
Two numbers whose difference is 16 2013-06-08
Johan pose la question :
Two numbers whose difference is 16 and whose sum is 120
Penny Nom lui répond.
1+2+4+8....= -1 2012-04-02
Andy pose la question :
In this minutephysics video, it's claimed that 1+2+4+8....= -1 Is this true, and if so, how?
< href="http://www.youtube.com/watch?v=kIq5CZlg8Rg">http://www.youtube.com/watch?v=kIq5CZlg8Rg

Robert Dawson lui répond.
Sum and difference of squares 2011-12-31
Anne pose la question :
Se x e y são números reais distintos, então:
a) (x^2 + y^2) / (x - y) = x + y
b) (x^2 + y^2) / (x - y) = x - y
c) (x^2 - y^2) / (x - y) = x + y
d) (x^2 - y^2) / (x - y) = x - y
e) Nenhuma das alternativas anteriores é verdadeira.

Harley Weston lui répond.
The sum of a series 2011-11-07
Rattanjeet pose la question :
Find the sum of 1(1/2) + 2(1/4) + 3(1/6) + 4(1/6)(3/4) + 5(1/6)(3/4)2 + 6(1/6)(3/4)3+ ... where 1/6 + (1/6)(3/4) + (1/6)(3/4)2 + ... constitutes a geometric series.
Penny Nom lui répond.
4 + 10 + · · · + (6n − 2) 2010-04-21
Lan pose la question :
Find the sum 4 + 10 + · · · + (6n − 2). The answer is 3(n^2) + n. How?
Penny Nom lui répond.
1/1+1/2+1/3... 2010-03-31
Mohd pose la question :
you explained the way of getting the summation of 100 series numbers but what is the summation of the numbers 1/1+1/2+1/3+1/4+1/5.............................+1/100
Robert Dawson lui répond.
1^3 + 2^3 + 3^3 +4^3 ... n^3 = ? 2010-01-29
ireimaima pose la question :
Hi..
Can u please help me with this question.. I find that when i test eg: n=2 for n (n+1) /4, it seems that it does not giving me the right answer of 1^3 + 2^3 = 9 but 3/2... i'm confuse..can u please help me..thanks so much

Prove that: 1^3 + 2^3 + 3^3 +4^3………………………………..n^3 = n (n+1) /4

Penny Nom lui répond.
Odds and evens in an n by n+1 table 2010-01-21
Shankar pose la question :
The boxes of an n * (n+1) table ( n rows and n+1 columns) are filled with integers. Prove that one can cross out several columns ( not all of them !) so that after this operation all the sums of the numbers in each row will be even.
Robert Dawson lui répond.
Summation Notation 2009-12-28
MANDIRA pose la question :
I want to get the formula for expressing one number by summation of consucutive numbers .
Janice Cotcher lui répond.
Jill and Bill 2009-11-04
Lisa pose la question :
Jill and Bill are two members of the Hill family. Jill is 8 years old and Bill is 9 years old. What will Bill's age be when the total of the digits in both their ages is once again 17?
Stephen La Rocque lui répond.
Arithmetic Sum & Sequence 2009-09-01
Alice pose la question :
Find the 24th term of this sequence 6.8,8.0,9.2... Find the sum of the first 21 terms
Janice Cotcher lui répond.
The sum of the angles of a triangle 2009-05-18
mary pose la question :
prove that the sum of the three angles inside any triangle always add up to 180 degrees?
Harley Weston lui répond.
The sum of the roots of a quartic 2009-04-21
dave pose la question :
This is a algebra problem that i am confused about: The sum of the roots of x^4-x^3+5x^2+4=0 is: i tried graphing it, but it shows that there are no roots, but the answer is 1. are they wrong?
Penny Nom lui répond.
The sum of the roots of a quartic 2009-01-03
peter pose la question :
How do you find the roots of an equation without graphing? like, i have a problem that says what is the sum of the roots of x^4-x^3+5x^2+4=0.
Harley Weston lui répond.
Determining the Unknown Numbers 2008-12-06
jacob pose la question :
the sum of two numbers is 45 and their difference is 15. what are the two numbers?
Janice Cotcher lui répond.
The distribution of sample sums 2008-11-21
Mark pose la question :
For large samples, the sample sum (Σ x) has an approximately normal distribution.
The mean of the sample sum is n*μ and standard deviation is (σ*√n). The distribution of savings per account for savings and loan institution has a mean equal to $750 and a standard deviation equal to $25. For a sample of 50 such accounts, find the probability that the sum in the 50 accounts exceeds $38,000.

Penny Nom lui répond.
Factoring 2008-11-19
Neji pose la question :
How do you factor (y-z) (y+z) (y^4+y^2z^2+z^4) and get (y+z)(y^2-yz+z^2) (y-z) (y^2+yz+z^2) as the answer?
Harley Weston lui répond.
Intercepts 2008-11-02
robert pose la question :
What is the sum of the x-intercept and y-intercept of the line 3x-3y=24?
Stephen La Rocque lui répond.
An arithmetic series 2008-10-17
Laura pose la question :
In an arithmetic series 5+9+13+...+tn has a sum of 945. How many terms does the series have? What formula do I use?
Penny Nom lui répond.
Factoring x^2 + 729 2008-08-19
peter pose la question :
hello I,am having trouble factorising a polynomial into polynomial factors with real coefficients please can you help the polynomial is x^2+729
Harley Weston lui répond.
Product of Two-Digit Numbers 2008-07-31
pete pose la question :
The number 4641 can be expressed as the product of two two-digit whole numbers. What is the sum of these two numbers?
Janice Cotcher lui répond.
Sum and product of the roots of a quadratic 2008-07-03
Gautam pose la question :
If a and b are the roots of x^2+px+1=0 and c and d are the roots of x^2+qx+1=0
prove that
(a-c)(b-c)(a+d)(b+d)=q^2-p^2
Regards
Gautam

Harley Weston lui répond.
The sum of the digits of two-digit number is 9 2008-07-01
Audrey pose la question :
the sum of the digits of two-digit number is 9. if the digits are reversed, the new number if 63 greater than the original number. find the number.
Penny Nom lui répond.
111...111 * 2003 2008-06-23
Peggy pose la question :
Number a = 111...111 formed by 2003 1's. Find the sum of the digits of the number 2003 * a.
Penny Nom lui répond.
The sum of the digits of a number 2008-06-23
Ben pose la question :
Question: Using mathematical induction, prove that if the sum of the digits of a number is divisible by three, then the number itself is also divisible by 3.
Penny Nom lui répond.
The sum and product of the roots of a quadratic 2008-03-16
Katelyn pose la question :
Write the quadratic equation....

Sum of the roots = 16
Product of the roots = -80

Penny Nom lui répond.
Sum and difference of cubes 2008-01-30
Amanda pose la question :
It has been a really long time since I was in Algebra and I can't remember how to factor cubes such as x^3 +81 or subtracting/adding fractions with variables such as [1/(x+h)+2]-[1/x+2]. Please help!!!
Penny Nom lui répond.
Total payments for a loan 2007-10-11
Robin pose la question :
A person is going to arrange a loan at 3 mill. he will pay 150000 back each year , so it take 20 yrs. to finish. In addition he pays 5% interest of what is leaft each year. How do I find the sum-function which shows the total sum he have payed?
Stephen La Rocque lui répond.
Sum and difference of two mystery numbers 2007-10-04
Donna pose la question :
The sum of two numbers is 39. The difference is 11. What are the numbers?
Stephen La Rocque lui répond.
T-totals 2007-09-26
Asma pose la question :
I wanted to know what i should include in my T-totals maths coursework and also how i should lay out the coursework?
Penny Nom lui répond.
Period of a sum of trig functions 2007-06-17
Aakash pose la question :
the period of the function f(x)=cos3x+sin4x+tan4x
Stephen La Rocque lui répond.
Buying topsoil 2007-05-16
Claudia pose la question :
I am trying to figure out if it is cheaper to buy topsoil by the bag (one 40lbs bag for $1.66) or having it delivered for $60 for 4 cubic yards.
Penny Nom lui répond.
The sum of two numbers is 30 2006-11-03
GG pose la question :
The sum of two numbers is 30 and the product of the same two numbers is 221. Find the two numbers.
Stephen La Rocque lui répond.
How does knowing the sum for 2+7 help you find the sum for 6+1 2006-10-26
Andrea pose la question :
How does knowing the sum for 2+7 help you find the sum for 6+1
Haley Ess lui répond.
The odd numbers from 30 to 80 2006-09-21
Kieran pose la question :
If you added all the odd numbers from 30 to 80, would the answer be even or odd? Explain.

I think it would be odd because I used this equation:
(30 x 5)+(40 x 5)+(50 x 5)+(60 x 5)+(70 x 5)+(25 x 5)=1325
I used the numbers for each set of ten -30 to 80 times 5 and the amount of the endings-1,3,5,7,9- added, times 5. Is that right?

Penny Nom lui répond.
What is the sum of the first 100 whole numbers? 2006-05-31
Jo pose la question :
what is the sum of the first 100 whole numbers?
Natasha Glydon, Paul Betts and Penny Nom lui répond.
Marine shipping - fuel consumption 2006-04-26
Sandy pose la question :
When a ship is 800 nautical miles from port its speed is reduced by 20%, thereby reducing the daily fuel consumption by 42 tonnes and arriving in port with 50 tonnes onboard. If the fuel consumption per hour is given by the expression (0.136 + 0.001V^3) where V is speed in knots; Estimate a) reduced consumption per day b) fuel onboard when speed reduced c) normal consumption for 800 nautical mile voyage d) increase in steaming time
Stephen La Rocque lui répond.
Adding consecutive numbers 2006-04-26
Lisa pose la question :
When I have a total that is the sum of consecutive numbers, how do I figure out what the numbers are?
Stephen La Rocque lui répond.
Proving a summation formula by induction 2006-04-19
Sharon pose la question :
Prove by induction that the sum of all values 2^i from i=1 to n equals 2^(n+1) - 2 for n > 1.
Stephen La Rocque lui répond.
Arithmetic Sums 2006-04-12
Angel pose la question :
(a) In a particular arithmetic sequence, u6 = 344.5 and u20 = 88.3. Find S28. (b) In a particular arithmetic series, S10 = 495 and S15 = 1005. Express S15 in sigma notation.
Stephen La Rocque lui répond.
Sum of a Geometric Sequence 2006-04-11
Andre pose la question :
In a particular geometric sequence, U3=-3.6 and U10=12.9. Find S16 and S17.
Stephen La Rocque lui répond.
Factor 2006-03-08
Brad pose la question :
Factor:
x3 + 64m3 and 125p3 - q6

Penny Nom lui répond.
Josh and John were both exposed to the flu 2005-12-16
Dudley pose la question :
Josh and John were both exposed to the flu. John has a 25% chance of getting it, while Josh has a 75% chance of getting it. What are the chances that at least one of them has the flu?
Penny Nom lui répond.
Adding improper fractions 2005-11-25
Paula pose la question :
I would like a simple step by step explanation on how to add improper fractions.
Penny Nom lui répond.
A block pyramid 2005-11-05
Kyle pose la question :
if i make a block pyramid and it puts a new perimeter around it every time, for example the first layer will be 1 block across (area=1), the second layer will be 3 blocks across (area=9), the third layer will be 5 blocks across (area=15),etc. The normal block pyramid. I have figured out that in order to figure out the number of blocks needed for a certain level, the equation is (2x-1)2 or (2x-1)(2x-1), where x is equal to the level. For example, on the fourth level, the equation tells you that it will have an area of 49. How would i make an equation for the total number of blocks up to the level. For example, in order to complete 1 level you need 1 block, for 2 levels you need 10 blocks, for three levels you need 35 blocks, and for 4 levels you need 84 blocks.
Penny Nom lui répond.
A sum of 75 and a difference of 13 2005-10-30
Vicki pose la question :
Find two numbers that have a difference of 13 AND A SUM OF 75? We need to learn about the formula or procedure.
Penny Nom lui répond.
What is the sum of the measures of the angles of a decagon? 2005-10-15
Dianna pose la question :
What is the sum of the measures of the angles of a decagon?
Penny Nom lui répond.
Two groups that have equal sums 2005-09-30
Anita pose la question :
using the numbers 1, 2, 3, 4, 5, 6, 7,and 8. how do we divide them into two groups so that they have equal sums?
Penny lui répond.
How to add three addends 2005-09-28
Patricia pose la question :

explaination of how to add three addends if you use a double to add or if you use a sum of 10

8+3+2=
6+4+0=
3+3+6=
2+5+4=


Baul Betts and Penny Nom lui répond.
The sum of a series 2005-08-31
Aamod pose la question :
Find the sum of the given series till n terms:

(14\1*3) + (24\3*5) + (34\5*7)............... till n terms

Chri Fisher lui répond.
A set of numbers whose sum is 1 2005-07-21
Santos pose la question :
Does there exist a set of numbers whose sum is 1, and the sum of whose squares is less than 0,01?
Paul Betts lui répond.
The sum of the digits of 2^100 2005-06-11
Richard pose la question :
The sum of the digits was calculated for the number 2100, then the sum of the digits was calculated for the resulting number and so on, until a single digit is left.
Penny Nom lui répond.
Adding consecutive integers 2005-05-13
Yas pose la question :
i need some help with my work which is to investigating sums of consecutive numbers for example: 15= 4+5+6 and 15=1+2+3+4+5
Penny Nom lui répond.
Two matrix problems 2005-03-30
Sue pose la question :
Question 1
Suppose all matrices in the equation below are square and invertible. Solve for x .

BA-1XB-1 + 2BA + In = 0 (the symbol "0" here denotes the matrix of all 0's in it)

Also, A-1 or B-1 is indicating inverse and "In" = for example, A-1 times A
I hope you understand the above. I have to show all the steps.

Question 2
Suppose we consider the set of all 2x2 matrices along with the operations of matrix addition and multiplication. Do they form a field? Why or why not?
I think the answer is no because under multiplication it is not commutative and not all square matrices are invertible. I not positive so I'd like some help.

Penny Nom lui répond.
A product equals a sum 2005-03-27
Tor pose la question :
Can you please help me with a general formula for the following system:
2+2=2*2
3+3/2=3*3/2
4+4/3=4*4/3

and how will you prove the formula?


Penny Nom lui répond.
The sum of the digits 2005-03-16
kelsey pose la question :
What is the sum of the digits in the decimal form of 21999 * 52002?
Claude Tardif lui répond.
A matrix construction problem 2005-03-14
Marcelo pose la question :
I want to know if is it possible to solve this problem:
I have an empty NxM matrix and I know totals (sum) by rows and totals by column.
Is there any algorithm to fill the matrix so that the summary of columns and rows gives the original values I have?

Harley Weston lui répond.
Sum to n terms of the series i.(2^(n-i)) 2005-01-28
Satya pose la question :
Sum to n terms of the series i.(2n-i)
Penny Nom lui répond.
1+3+5+...+(2n+1) 2004-09-10
Emma pose la question :
Prove that 1+3+5+...+(2n+1)= (n+1)2
Penny Nom lui répond.
Factoring 2004-07-19
A student pose la question :
Factor completely:
3x3 - 24y3
54x6 + 16y3
16xy - 4x - 4y - 1
0.09x2 - 0.16y2

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.
The sum of 4,0,-4..., -156 2004-04-28
Christina pose la question :
find the requested sum of the arithmetic sequence

4,0,-4..., -156

Penny Nom lui répond.
Factoring 2004-04-27
Bipin pose la question :
FACTORISE:

a to the power of 6 + b to the power of 6

Penny Nom lui répond.
Some factoring problems 2004-04-15
KJ pose la question :

Factor these:
x3+125 -----> (x+5)3
8x3-27 -----> (?)
x2+36 -----> (x+6)2
x4-5x2+4 --> (?)


Penny Nom lui répond.
Sum of the angles in a pentagon 2004-03-11
Ashish pose la question :
What is the sum of all the measures of the angles of a Pentagon
Penny Nom lui répond.
Sums and differences 2004-02-10
David pose la question :
The sum of two whole numbers is 63. The difference between the numbers is 10. Find all the possible pairs.
Claude Tardif and Penny Nom lui répond.
The sum of two numbers is 5 and their difference is 2003-06-16
Akhil pose la question :
The sum of two numbers is 5 and their difference is 11. What is the product of the two numbers?
Penny Nom lui répond.
positive multiples of 10 that are the sum of four consecutive integers 2003-05-01
Taurus pose la question :
How many positive multiples of 10 that are less than 1000 are the sum of four consecutive integers?
Penny Nom lui répond.
Three digit number 2003-03-10
Grace pose la question :
What three digit positive integer is exactly 32 times the sum of its digits?
Claude Tardif lui répond.
Factoring 2002-12-11
Larry pose la question :
Question:

how do u factor trinonmials

EX: X 3 + Y 3

X 3 - 8Y 3

8X 2 - 72

64A 3 - 125B 6

Penny Nom lui répond.
Factor completely 2002-11-21
Shelley pose la question :
these two questions are to be factored completely but i have no idea how to factor them
  1. (x-4y) 2 - 3(x-4y) - 4
  2. x 6 + y 6

Penny Nom lui répond.
Fuel consumption 2002-11-11
Guy pose la question :
When a car is driven 'normally' the feul consumption is 7.5 per litres per 100km. On a particular journey the car was driven in 'hard' and the consumption changed to 9.1 litres per 100km. Fuel cost 80p per litre. Calculate:

a) The extra feul consumed.
b) The extra cost of feul, in pounds, for the journey when the car was driven in 'hard'.

Penny Nom lui répond.
Sums of evens 2002-09-14
Rosa pose la question :
How do I find a geometric way to easily compute sums of consecutive even numbers 2 + 4 + 6 + ....
Leeanne Boehm and Harley Weston lui répond.
7+8+9+...+1000 2002-09-11
Shirley pose la question :
My question is what is the formula for adding up numbers when you don't start with number 1? For example 3 + 4 + 5 + 6 = 18. But how could you arrive at the answer without adding all the numbers?
Penny Nom lui répond.
The sum of the first one hundred even numbers 2002-09-10
Arthur pose la question :
What is the sum of the first one hundred even numbers?
Penny Nom lui répond.
The sum of the areas of two regular decagons 2002-05-27
A parent pose la question :
The sum of the areas of two regular decagons is 39 square inches, and their radii are in the ratio of 2:3. Find the area of the larger decagon.
Paul Betts lui répond.
Arithmetic progressions 2002-04-24
David pose la question :
I have been searching everywhere for the formula to mathamatical progression.
Penny Nom lui répond.
24x^4 + 3x 2002-03-18
gary pose la question :
24x 4 + 3x
Penny Nom lui répond.
1+2+3+...+1000 2001-10-01
Louise pose la question :
Find a quick way to add all Intergers (whole Numbers) between 1 and 1000?
Walter Whiteley lui répond.
Conservation, consumption and population growth 2001-06-04
Steve pose la question :
I'm trying to quantify the relation between conservation/consumption and population growth. For instance let's consider California:

The 2000 census states that California's population grew from 29,760* in 4-1990 to 33,871 in 4-2000. I want to find r or rate of growth per year. Based on the exponential growth formula for population growth:
.
.
.


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.
National consumption function 2001-05-09
Brian pose la question :
If consumption is $11 billion when disposable income is 0 and the marginal propensity to consume is dC/dy = 1/(2y+4)1/2+0.3(in billions of dollars), find the national consumption function.
Harley Weston lui répond.
Sigma 2001-03-31
A student pose la question :
What does the Sigma symbol mean in mathematics?
Penny Nom lui répond.
The sum of all ten-digit numbers. 2001-01-10
John pose la question :
Compute the sum of all ten-digit numbers. Can you determine the sum of all n -digit numbers?
Sukanta Pati lui répond.
A dollar, quarter, dime, nickle and penny 2001-01-07
Sarah pose la question :
Arnold has a dollar coin, one dime, one quarter, one nickel, and a penny. The number of different sums of money that can be formed using three coins is...
Penny Nom lui répond.
Infinite Geometric Series 2000-11-10
Sam Carter pose la question :
I ran into a problem when studying how to find the sum of an infinite geometric series. My math book attempts to explain the concept by giving formulas involving sigma and |r|, but it does not really explain how to go about finding the sum of an infinite geometric series. If you could either help me with this or point me in the direction of an informative website that could help me, I'd appreciate it.
Harley Weston lui répond.
The sum of the cubes is the square of the sum 2000-10-10
Otoniel pose la question :
Without using mathematical induction, or any other method discovered after 1010 a.d. , prove that the sum of i3, (where i, is the index of summation) from one to, n, is equal to ((n*(n+1))/2)2
Penny Nom lui répond.
1 + 2 + 3 + ... + 50 2000-09-14
Vicki Charron pose la question :
How can you calculate the total of the numbers one through fifty, without adding up the individual numbers?
Penny Nom lui répond.
The sum of the squares of 13 consecutive positive integers 2000-08-25
Wallace pose la question :
Prove that it is not possible to have the sum of the squares of 13 consecutive positive integers be a square.
Harley Weston lui répond.
Riemann sums 2000-03-30
Joshua D. Parham pose la question :
If n is a positive integer, then
 
     lim   (1/n)[1/(1+1/n) + 1/(1+(2/n) + ... + 1/(1+n/n)] 
n->infinity 

can be expressed as the integral from 1 to 2 of 1/x dx
Penny Nom lui répond.

The sum of the cubes is the square of the sum 1999-08-25
Bernard Yuen pose la question :
How to prove 13 + 23 + 33 + 43 + ... n3 is equal to (1+2+3+...n)2? (for n is positive integer)
Harley Weston lui répond.
Compound Interest 1999-07-01
Kim Palmer pose la question :
In early 1997, my son borrowed $4831 at 7.5%. He has made 30 monthly payments of $130 each. He is now in a position to pay off the balance. What is his remaining principal?
Penny Nom lui répond.
Factoring 1999-03-30
Maggie Stephens pose la question :
I don't know anything about factoring would you plese help me.

3x4 - 48

54x6 + 16y3

125-8x3

12x2 - 36x + 27

9 - 81x2

a3 + b3c3

I would greatly appreciate any help you can give me thanks.
Jack LeSage 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