GMAT Prep1

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Source: — Data Sufficiency |

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by lokesh r » Sat Sep 25, 2010 1:19 pm
lokesh r wrote:Help!
I am clueless about how to approach this problem.Please help me guys..

Here is the attachment for the quesion.


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by this_time_i_will » Sun Sep 26, 2010 6:28 am
i hope it is quite clear that I and II alone are not sufficeint.

Including both I and II:
stmt II says that distance b/w t & r is same as distance b/w t and -s. now, -s can not be to the right of t because s is positive and -s would be negative. So, -s is to the left of t. So where should i put -s to the left of t, so that stmt II is in agreement. obviously, -s sud fall on r. That means point r and -s are actually one-and-same.

so, the number line is something like this:

----(-s)----------0-------------(s)------t

And yes, 0 is halfway b/w s and -s..i..e. half way b/w s and r. (remember r and -s are one-and-same)