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Source: — Data Sufficiency |

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by Anurag@Gurome » Thu Jan 26, 2012 7:41 am
sud21 wrote:Is x an integer?
1). x^1/3 is an integer
2). x^1/2 is not an integer
Statement 1: As x^(1/3) is an integer, (x^(1/3))^3 = x will be an integer too.

Sufficient

Statement 2: As x^(1/2) is not an integer, (x^(1/2))^2 = x may or may not be an integer.
For example, 5^(1/2) is not an integer but 5 is but 4^(1/2) and 4 both are integers.

Not sufficient

The correct answer is A.
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by mj78ind » Thu Jan 26, 2012 7:44 am
sud21 wrote:Is x an integer?
1). x^1/3 is an integer
2). x^1/2 is not an integer
Stmt 1 => (X)^(1/3) = i where I = integer.
Thus, x = i^3, which has to be an integer. SUFFICIENT.

Stmt 2 => (x)^(1/2) = n where n = non integer,
Thus x = n^2, if n = (13)^(1/2), then x = 13 hence x is an integer, however if n = (13)^(1/4), x = (13)^(1/2) a non integer. Hence NOT SUFFICIENT.

Hence A
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by ArunangsuSahu » Thu Jan 26, 2012 12:12 pm
Statement 1:
x^1/3 is an integer => x is an integer. SUFFICIENT

Statement 2:
Take x=1.21 and x=2...Not Sufficient
(A) is the answer
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