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Ankur87
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Q is less than 10. Is Q a prime number?
Q2 - 2 = P; P is prime and P < 10.
Q + 2 is NOT prime, but Q is a positive integer.
A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D) EACH statement ALONE is sufficient.
E) Statement (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data are needed.
IMO : A
because:
Q^2 - 2 = P ( P = Prime, P < 10)
2^2 - 2 = 2 ( 2 is a Prime number and < 10 )
3^2 - 2 = 7 ( 7 is a Prime number and < 10 )
So Q is prime.
A is sufficient.
B is not sufficient as
(Q + 2 = 2+2 = not prime)
(Q + 2 = 4+2 = not prime)
2 is prime , 4 is not prime.
So we can't say if Q is prime or not.
But OA is C
Please explain.
Q2 - 2 = P; P is prime and P < 10.
Q + 2 is NOT prime, but Q is a positive integer.
A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D) EACH statement ALONE is sufficient.
E) Statement (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data are needed.
IMO : A
because:
Q^2 - 2 = P ( P = Prime, P < 10)
2^2 - 2 = 2 ( 2 is a Prime number and < 10 )
3^2 - 2 = 7 ( 7 is a Prime number and < 10 )
So Q is prime.
A is sufficient.
B is not sufficient as
(Q + 2 = 2+2 = not prime)
(Q + 2 = 4+2 = not prime)
2 is prime , 4 is not prime.
So we can't say if Q is prime or not.
But OA is C
Please explain.
