Questions about the world of GMAT Math from other sources and general math related questions.
2amitprakash
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Subtraction rules encountered for a DS question

by 2amitprakash Sun Sep 13, 2009 1:23 am

Since the DS question is from official guide, I'm not putting the question in entirety but need to discuss the concept used.
Information in Question: 3 numbers - k, l, m; no other information like k,l,m NE 0 or integers or anything else.
Test condition concept: k-(l+m) can be equal to (k-l)+(k-m) if and only if k=0 but can never be equal for any other value of k - True or False? For me it is True.
ganeshraj
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Re: Subtraction rules encountered for a DS question

by ganeshraj Tue Sep 15, 2009 5:41 am

K-(l+m) = (K-l)+(K-m)
k-(l+m) = 2K-(l+m)
k=2K

K must be 0.
RonPurewal
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Re: Subtraction rules encountered for a DS question

by RonPurewal Thu Oct 01, 2009 6:28 am

ganeshraj Wrote:K-(l+m) = (K-l)+(K-m)
k-(l+m) = 2K-(l+m)
k=2K

K must be 0.

perfect.