For any positive integer n, the sum of the first n positive integers equals n(n+1)/2. What is the sum of all the even integers between 99 and 151?
Select:
A) 2050 B) 2350 C) 2650 D) 2950 E) 3250
100 + 102 + ... + 150 =   100*26 + (2+4+...+50) =   100*26 + 2*(1+2+...+25) =   100*26 + 2(25)(26)/2 =   100*26 + 25*26 = 125(26) = 3250   The answer is 3250.
<result>E</result>
For any positive integer n, the sum of the first n positive integers equals n(n+1)/2. What is the sum of all the even integers between 99 and 151?