Prime Number

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Prime Number

by GmatKiss » Sat May 19, 2012 10:16 pm
If x is an integer, is x a prime number?

1) x is a multiple of a prime number
2)x is a product of two integers

IMO: A

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by neelgandham » Sun May 20, 2012 3:31 am
If x is an integer, is x a prime number?
1) x is a multiple of a prime number
If x = 2, x is a multiple of a prime number, an integer and a prime number.
If x = 4, x is a multiple of a prime number, an integer and NOT a prime number.
Statement 1 isn't sufficient to answer the question.
2)x is a product of two integers
If x = 2, x is a product of two integers (2*1), an integer and a prime number.
If x = 4, x is a product of two integers (2*2), an integer and NOT a prime number.
2)Statement 1 + 2
If x = 2, x is a product of two integers (2*1) ,a multiple of a prime number, an integer and a prime number.
If x = 4, x is a product of two integers (2*2), a multiple of a prime number, an integer and NOT a prime number.

IMO E
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by Anurag@Gurome » Sun May 20, 2012 9:41 pm
GmatKiss wrote:If x is an integer, is x a prime number?

1) x is a multiple of a prime number
2)x is a product of two integers

IMO: A
(1) x is a multiple of a prime number.
If x = 2, then x is a prime number.
If x = 4, then x is not a prime number.
No definite answer; NOT sufficient.

(2) x is a product of two integers.
If x = 2 * 1 = 2, then x is a prime number.
If x = 2 * 2 = 4, then x is not a prime number.
No definite answer; NOT sufficient.

Combining (1) and (2), we can take same examples as in statements 1 and 2 above; NOT sufficient.

The correct answer is E.
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by GmatKiss » Mon May 21, 2012 4:18 am
Thanks,

Note that, X can also be negative!!

OA is E