is rst=1

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is rst=1

by djkvakin » Wed Dec 09, 2009 4:12 pm
Is R*S*T=1?
I: R*S=1
II: S*T=1

The answer is E, which is obvious, but PLEASE HELP ME UNDERSTAND THE LOGIC OF TEST GIVERS!!!! My answer is C, but when I say it's C, I mean that R*S*T DOES NOT equal to 1 taken both conditions together. We can say with certainty that when I and II taken together, the product of R S and T will NOT equal to 1. So our answer to the question if R*S*T=1, is a definite NO, and we discovered that by applying both conditions together.
Am I going crazy?

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by Testluv » Wed Dec 09, 2009 4:40 pm
djkvakin wrote:Is R*S*T=1?
I: R*S=1
II: S*T=1

The answer is E, which is obvious, but PLEASE HELP ME UNDERSTAND THE LOGIC OF TEST GIVERS!!!! My answer is C, but when I say it's C, I mean that R*S*T DOES NOT equal to 1 taken both conditions together. We can say with certainty that when I and II taken together, the product of R S and T will NOT equal to 1. So our answer to the question if R*S*T=1, is a definite NO, and we discovered that by applying both conditions together.
Am I going crazy?
Why do you think you have a definite No? Can't all of R, S, and T just equal 1? (I guess maybe you're assuming that R, S, and T are necessarily distinct?) And, to be clear, if you ever do get a definite no answer to a yes/no DS question, then you have sufficiency.
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by raj_aabr » Thu Dec 10, 2009 1:24 pm
Is R*S*T=1?
I: R*S=1
II: S*T=1


S1) There is no information about "T" ---> Insufficient.
S2) There is no information about "R" ---> Insufficient.

Combined.
There is condition given so you can assume any numbers.
Assume R=1, S=1 and T=1 -----> The ans is YES, but,
if R=6, S=1/6 and T=6 -------> Then the ans is NO.

So the ans E.