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Number Systems -Odds & Evens

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Source: — Data Sufficiency |

by Brent@GMATPrepNow » Wed Oct 16, 2013 10:39 am
sukhman wrote:If x and y are positive integers and 3x + 5 < x + 11, is x a prime number?
(1) The sum of x and y is even. (2) The product of x and y is odd.
I assume that one of the variables above must be y?

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Brent
Brent Hanneson - Creator of GMATPrepNow.com
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by sukhman » Wed Oct 16, 2013 11:27 pm
even I am confused because it had been solved using x only in the solutions
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by theCodeToGMAT » Thu Oct 17, 2013 12:53 am
Assuming question is correct
3x + 5 < x + 11
2x < 6
x < 3
x = 1 or 2

To find: x=2?

Statement 1:

x + y = EVEN
No info of "y"
INSUFFICIENT

Statement 2:
xy = ODD
this means both x & y are ODD
so, x is "1"
SUFFICIENT

Answer [spoiler]{B}[/spoiler]
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