SOLUTION: I know there is a simpler way of doing this problem other than replacing the variable with each consecutive integer until they add up to 300, because I tried that and they didn't a
Algebra.Com
Question 177700: I know there is a simpler way of doing this problem other than replacing the variable with each consecutive integer until they add up to 300, because I tried that and they didn't add up. I would appreciate any help with this problem.
"The sum of the consecutive integers 1,2,3, ..., n is given by the formula . How many consecutive integers, starting with 1, must be added to get a sum of 300?"
Found 2 solutions by stanbon, gonzo:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
S(n) = (1/2)*n(n+1). How many consecutive integers, starting with 1, must be added to get a sum of 300?
---------------------
Equation:
(n/2)(n+1) = 300
Multiply both sides by 2 to get:
n(n+1) = 600
n^2 +n - 600 = 0
(n-25)(n+24) = 0
Positive solution:
n = 25
=============
Cheers,
Stan H.
Answer by gonzo(654) (Show Source): You can put this solution on YOUR website!
you just set the equation to 300 and solve for n as follows:
n*(n+1)/2 = 300
(n^2 + n)/2 = 300
multiply both sides by 2 to get:
n^2 + n = 600
subtract 600 from both sides to get:
n^2 + n - 600 = 0
this is a quadratic equation.
factor to get:
(n+25) * (n-24) = 0
n = -25
or
n = 24
since n has to be positive, the only answer can be n = 24
substitute in original equation to get:
n * (n + 1)/2 = 300
which becomes:
(24*25)/2 = 300
which becomes:
600/2 = 300
which becomes:
300 = 300
equation is true so the value of n = 24 is good.
your answer is:
the number of consecutive integers, starting with 1, added together to get a sum of 300, is 24.
---
RELATED QUESTIONS
I know this is a very basic question, but I cannot remember if there is any way of... (answered by stanbon)
I didn't know what category to put this in...
Solve for 4+8+12+...+204+208 is there a... (answered by mananth)
Please help. I've been trying to solve this problem: Find two consecutive odd integers... (answered by palanisamy,richwmiller)
Please help. I've been trying to solve this problem: Find two consecutive odd integers... (answered by richwmiller)
This is a digit and coin word problem. I know how to do simpler digit and coin problems... (answered by Edwin McCravy)
i'm having problem finding the domain ... is there a simpler way to find the domain?... (answered by stanbon)
Define a variable,write an equation and solve the problem: Find two consecutive odd... (answered by bucky)
Please Help me solve this word problem...
Camille has 19 coins consisting of nickels,... (answered by stanbon,Alan3354)
is there a simpler way to explain this to me cause im still... (answered by jim_thompson5910)