If x and y are integers greater than 1 and x>y . . . .

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If x and y are integers greater than 1 and x>y, what is the value of x?

1) x+y=10
2) xy=21

The OA is the option B.

Why is sufficient the statement (2)? It says that x=3 or x=7, so is not sufficient. I am confused.

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by Brent@GMATPrepNow » Sat Jan 13, 2018 11:21 am
M7MBA wrote:If x and y are integers greater than 1 and x>y, what is the value of x?

1) x+y=10
2) xy=21
Target question: What is the value of x?

Given: x and y are integers greater than 1 and x > y

Statement 1: x+y=10
There are several values of x and y that satisfy statement 1. Here are two:
Case a: x = 9 and y = 1. In this case, the answer to the target question is x = 9
Case b: x = 8 and y = 2. In this case, the answer to the target question is x = 8
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: xy=21
Since x and y are INTEGERS greater than 1 AND x > y, we can see that it MUST be the case that x = 7 and y = 3
Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Answer: B

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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