Hi rajthakkar,
This question is perfect for TESTing VALUES (and knowing a few specific Number Properties would likely help).
**NOTE: I'm going to assume that this question has just 2 variables: P and Q; any difference in capitalization/lower-case in the original prompt is an oversight**
We're told that P and Q are NON-NEGATIVE. We're asked if P+Q > (P)(Q). This is a YES/NO question.
Fact 1: P = Q
IF...
P=Q=0
Then 0+0 is NOT > (0)(0) and the answer to the question is NO.
IF....
P=Q=1
Then 1+1 IS > (1)(1) and the answer to the question is YES.
Fact 1 is INSUFFICIENT.
Fact 2: P + Q > P^2 + Q^2
In this Fact, while one of the variables COULD be 0, they CANNOT BOTH be 0. This means that one or both of the variables must be POSITIVE (but they both have to be relatively SMALL, they CAN'T BOTH be 1 and they CAN'T BOTH be greater than 1, otherwise the inequality won't hold true).
At this point, you might recognize some Number Properties or you might want to prove your ideas by TESTing VALUES. Here, one or both of the numbers will be a fraction. The Number Property in question is that since one (or both) are positive fractions, P+Q will always be > than (P)(Q), since multiplying a positive by a fraction makes the product SMALLER.
IF...
P = 1/2
Q = 0
Then 1/2 + 0 IS > (1/2)(0) and the answer to the question is YES.
IF...
P = 1
Q = 1/2
Then 1 + 1/2 IS > (1)(1/2) and the answer to the question is YES.
IF...
P = 1.1
Q = 1/2
Then 1.1 + 1/2 IS > (1.1)(1/2) and the answer to the question is YES.
Fact 2 is SUFFICIENT
Final Answer:
GMAT assassins aren't born, they're made,
Rich