GMATPrep,pls,help

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GMATPrep,pls,help

by tanviet » Wed Dec 23, 2009 7:21 pm
This is from GMATPrep, pls help

<-----------r------------s---------t-------->

on the number line shown, is zero haft way between r and s

a, s is to the right fo zero

b, the distance between t and r is the same as distance between t and -s

OA is C,(both statement is needed)

why so, B is ok.pls, help

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by papgust » Thu Dec 24, 2009 3:00 am

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by yserious » Thu Dec 24, 2009 6:08 am
papgust wrote:Check this solution from Ron,
https://www.manhattangmat.com/forums/is- ... t4202.html
Jus saw the solution there..

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the particular trap you've fallen into in your interpretation of (2) is that of assuming "-s" is to the LEFT of "t". there is no good reason whatsoever to make this assumption, and, what's more, at least one good reason (viz., "the gmat loves to test exactly these sorts of assumptions) not to make it.
of course, you don't need reasons to be very careful about your assumptions; that should be your default state.

if "-s" is to the right of "t", then you have
<--r-------s---t-----------(-s)-->
in which case 0 is in no-man's-land between "t" and "-s".
in this case, note that "s" is negative. also note that (-s) is positive in this case, a situation that is difficult to digest for most students

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i wanna know, how can the distance between t and -s be equal to the distance between t and r when -s is to the LEFT of "t"
my assumption is that -s could not be on the right of t for the distance between t and r to be same as distance between t and -s

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by yserious » Sat Dec 26, 2009 12:26 am
Can somebody pls help here?

how can the distance between t and -s be equal to the distance between t and r when -s is to the LEFT of "t"
my assumption is that -s could not be on the right of t for the distance between t and r to be same as distance between t and -s