Divisibility/Primes: Which of the following is the product

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Which of the following is the product of two integers whose sum is 11 ?

(A) -42
(B) -28
(C) 12
(D) 26
(E) 32

My question is what TWO different approaches can you use to solve this question quickly.
What would be the first thing that enters your mind when you see this question in the GMAT exam ?

Thanks.
Last edited by II on Mon May 05, 2008 1:49 am, edited 1 time in total.
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by Kaunteya1 » Tue Apr 01, 2008 2:27 pm
Well the first thing that pops into my mind when I see a question like this is that you have to determine what two numbers multiplied together from each a-e could possible form 11 when added.

a) 14x-3 = -42
14+-3 = 11
b) 14x-2 = -28
14+-2= 12
-7x4 = -28
-7+4 = 3
c) and so on.

Shouldn't take too long under 2 minutes for sure.