SOLUTION: How do you find the sum of the odd numbers from 19 to 101. I need a formula to turn in.

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: How do you find the sum of the odd numbers from 19 to 101. I need a formula to turn in.      Log On


   

Question 1076690: How do you find the sum of the odd numbers from 19 to 101. I need a formula to turn in.
Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!
S1 = 1
S2 = 1+3 = 4
S3 = 1+3+5 = 9
…
Sn = 1+3+5+…+(2n-1) = n%5E2
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The sum you want to find is that for 2n-1 = 101 —> n=51
then you will want to subtract the sum for 2n-1 = 19 —> n=10
Can you work it out?
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My answer assumes you want to exclude 19, if it is included, adjust accordingly.