certain sequence is given

This topic has expert replies
User avatar
GMAT Instructor
Posts: 3650
Joined: 21 Jan 2009
Location: India
Thanked: 267 times
Followed by:80 members
GMAT Score:760

certain sequence is given

by sanju09 » Wed Apr 08, 2009 4:14 am
For any 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 of 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

The mind is everything. What you think you become. -Lord Buddha

Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad


Senior | Next Rank: 100 Posts
Posts: 53
Joined: 09 Feb 2009
Thanked: 1 times

by kaf » Wed Apr 08, 2009 4:20 am
This question has been answered and explained thoroughly here

https://www.beatthegmat.com/gmat-prep-qu ... 21502.html