If X and Y are prime integers, what is X+Y?

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by Jay@ManhattanReview » Tue Apr 24, 2018 12:16 am
Gmat_mission wrote:If X and Y are prime integers, what is X+Y?

1. X-Y is a prime integer
2. Y<X<6

[spoiler]OA=E[/spoiler].

I think using both statements together is sufficient. Why is E the correct answer? May someone helps me? Thanks.
Given X and Y are prime integers, we have to get the value of X + Y.

Let's take each statement one by one.

1. X - Y is a prime integer.

Case 1: If X = 5 and Y = 3, then X - Y = 5 - 3 = 2, a prime integer. X + Y = 5 + 3 = 8.
Case 2: If X = 5 and Y = 2, then X - Y = 5 - 2 = 3, a prime integer. X + Y = 5 + 2 = 7. No unique answer. Insufficient.

2. Y < X < 6

Both the cases discussed in Statement 1 are applicable here too. So, even the combination of the two statements does not help.

The correct answer: E

Hope this helps!

-Jay
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