inclusive

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inclusive

by baller12q » Sat Mar 28, 2009 12:29 pm
if A equals the sum of the even intergers from 2 to 20 inclusive, and B equals the sum of the odd intergers from 1 to 19 inclusive, what is the value of A-B

i got this question wrong and need to undestand it
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Re: inclusive

by Brent@GMATPrepNow » Sat Mar 28, 2009 1:47 pm
baller12q wrote:if A equals the sum of the even intergers from 2 to 20 inclusive, and B equals the sum of the odd intergers from 1 to 19 inclusive, what is the value of A-B

i got this question wrong and need to undestand it
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by shargaur » Tue Apr 07, 2009 6:33 pm
A = Arithmetic progression with a=2 l=20 n=10
A= 10/2(2+20) = 110
B = Arithmetic progression with a=1 l=19 n=10
B= 10/2(1+19) = 100

A - B = 10