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 201? Choose the correct answer.
A) 7650	B) 9250	C) 12,650	D) 14,250	E) 15,150
100 + 102 + ... + 200 =   100*51 + (2+4+...+100) =   100*51 + 2*(1+2+...+50) =   100*51 + 2(50)(51)/2 =   100*51 + 50*51 = 150(51) = 7650   The answer is 7650.
<result>A</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 201?