Sum series

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Sum series

by ruplun » Fri Jul 15, 2011 6:37 am
For every integer k from 1 to 10, inclusive,the kth term of a certain sequence is given by (-1)^(k+1)(1/2^k) . If T is the sum of the first 10 terms in the sequence , then T is

a. greater than 2
b. between 1 and 2
c. between 1/2 and 1
d. between 1/4 and 1/2
e. less than 1/4
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by GMATGuruNY » Fri Jul 15, 2011 6:50 am
ruplun wrote:For every integer k from 1 to 10, inclusive,the kth term of a certain sequence is given by (-1)^(k+1)(1/2^k) . If T is the sum of the first 10 terms in the sequence , then T is

a. greater than 2
b. between 1 and 2
c. between 1/2 and 1
d. between 1/4 and 1/2
e. less than 1/4
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