1) x(y+5) is an even integer
if y is odd, x can be even or odd and the result will be even.
INSUFF
2) 6y^2 + 41y + 25 is an even integer
In order for this to be an even integer y must be odd. However, this tells us nothing about x.
INSUFF
Combined:
From statement 2 we know that y is odd. From statement 1 we know if y is odd, x can be even or odd.
INSUFF
I choose E.
Positive even integers
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Source: Beat The GMAT — Data Sufficiency |
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fighting_cax
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I got lost in this part. How were you able to derive that y must be odd based on the equation given?dmateer25 wrote:
2) 6y^2 + 41y + 25 is an even integer
In order for this to be an even integer y must be odd. However, this tells us nothing about x.
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cramya
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Hoping Dmateer will not mindI got lost in this part. How were you able to derive that y must be odd based on the equation given
Rules:
odd+odd = even
even+even=even
even+odd = odd
Same rules above apply to subtraction also
even*even = even
odd*odd=odd
even*odd = even
6y^2+41y+25(ODD) -> even
6y^2 - >always even no matter if y is even or odd
So we now have
6y^2(EVEN) + 41y+ ODD = EVEN
6y^2(EVEN)+25(ODD) = ODD
Therefore the above reduces to
ODD + 41y = even
y has to be odd since only ODD+ODD = EVEN
For 41y to be odd, y has to be odd based on multiplication rules above
Hope this helps!
Regards,
CR
