SOLUTION: The sum of ten consecutive multiples of fours is 140. What is the largest of the ten numbers?

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Question 890394: The sum of ten consecutive multiples of fours is 140. What is the largest of the ten numbers?
Found 2 solutions by Fombitz, MathTherapy:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!

4%28N-5%2BN-4%2BN-3%2BN-2%2BN-1%2BN%2BN%2B1%2BN%2B2%2BN%2B3%2BN%2B4%29=140
4%2810N-5%29=140
40N-20=140
40N=160
N=4
The largest is
%28N%2B4%294=%284%2B4%294=8%2A4=32

Answer by MathTherapy(10858) About Me  (Show Source):
You can put this solution on YOUR website!
The sum of ten consecutive multiples of fours is 140. What is the largest of the ten numbers?
Use the formula for the sum of an arithmetic progression (AP) to determine the value of a%5B1%5D, the 1st term. 

Be reminded that d, or the common difference is 4, since the terms differ by 4 (the terms are CONSECUTIVE multiples of 4)

Using a%5B1%5D or the value of the 1st term, determine a%5B10%5D, or the value of the 10th term.