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What is the sum of the odd numbers from 1 to 73 (including 73)?

What is the sum of the odd numbers from 1 to 231?

Guest Jul 6, 2018

#1**0 **

N =(L - F) / D +1, where N=Number of terms, L=Last term, F=First term, D=Common difference.

N=(73 -1) / 2 + 1

N =37 terms

Sum = (F + L) / 2 x N

Sum = (1 + 73) / 2 x 37

**Sum =1,369**

Do exactly the same thing with numbers 1 to 231. If you don't make any mistakes, you should get:

**Sum =13,456**

Guest Jul 6, 2018