Is rst = 1?

Question

Is rst = 1 ? (1) rs = 1 (2) st = 1 OPEN DISCUSSION OF THIS QUESTION IS HERE: is-rst-90398.html

cool_jonny009 · Answer

E.

Is rst = 1?

1) rs = 1
product of rs is given so rst depends on t Not Sufficient
cause let r =2 s =1/2 so rs =1 but do information about t ....so INSuff

2) st = 1
same explanation as 1 ...INSuff

taken togther also ...get differnt value 
for example let r =2 , s=1/2, t =2 satisfy both condition but give answer NO
and r=1,s=1,t=1 satisfy both conditon bu gives answer Yes ...so Insuff

hence E

GMATT73 · Answer

Yes, if S is a fraction, then both statements are insuff.

duttsit · Answer

another number to pick in this case is:

r=s=t = -1

sudhagar · Answer

OA is E and good explanation cool_jonny009.

Just posted the question so that members do not fall for the trap by not considering fractions or negative 1 (-1).

cachaval · Answer

One Q! When I was solving this question I thought that if there were 3 different letters then the 3 numbers should be different, but by the answers given to this question in this forum it seems that I was wrong. It looks as if even though we are given 3 different letters any of these could have the same value, can someone confirm this? I´ve tried looking "same letters" in the forum search but nothing came up, sorry if this was answered elsewhere.

Thanks in advance.

Thanks in advance.

Bunuel · Answer

Unless it is explicitly stated otherwise, different variables CAN represent the same number. OPEN DISCUSSION OF THIS QUESTION IS HERE: is-rst-90398.html

Is rst = 1?

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