OG 12 DS - Q100

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OG 12 DS - Q100

by jainrahul1985 » Thu Apr 22, 2010 8:58 pm
If [x] denotes the greatest integer less than or equal to x , is [x] = 0 ?
(1) 5x+1 = 3 +2x
(2) 0<x<1

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by rn4gmat » Thu Apr 22, 2010 9:20 pm
IMO the answer to this will be D as from each of the two statements it can be inferred that [x] =0

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by el_torero » Thu Apr 22, 2010 9:23 pm
My answer is D.

my interpretation of definition of [x] is that [x] is the closest integer <= x.

(1) 5x+1 = 3 +2x

you can solve for x. then you can find [x].

namely, that x = 1/2. so [x] = 0. note that you don't even need to solve for x explicitly. it's good enough you are able to find x because then you can find [x].

SUFF


(2) 0<x<1

any value of x that satisfies (2) will yield [x] = 0. SUFF.

hope this is correct :)

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by tpr-becky » Thu Apr 22, 2010 10:11 pm
for the first statement, i fyou can solve for x then, no matter what the value is, you can determine wehtehr [x]=0 becuase you will know the exact answer (it really doesn't even matter which is the answer)

AD

for the second statement you know that x is a fraction between 0 and 1 which means that the greatest integer less than x will always be 0.

So the answer is D
Becky
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