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.
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Number Systems -Odds & Evens
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I assume that one of the variables above must be y?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.
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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]
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]
R A H U L
