x+y+z is even, is x*y*z even? 1) x*y even 2) y*z odd

Question

x+y+z is even, is x*y*z even?
1) x*y even 
2) y*z odd

Ozmba · Answer

x+y+z is even, is x*y*z even?

This is always true..bcos for X+Y+Z to be true 

one case : two of the three variable have to be odd and one even 

second case : All the three have to be even...

so x*y*z will always be even.....

Please check the question and let us know

christoph · Answer

the question doesnt state that x and y and z have to be integers...

Antmavel · Answer

Agree with Christophe.

However, and to to asnwer the question, I will consider that x,y and z are considered as integers.

I would answer D

1) x*y even 
if XY is even, XYZ is always even.
it doesn't matter if Z is odd or even because any number multiplied by any even number = EVEN
suff

2) y*z odd which means both numbers are odd
We know that x+y+z is even so the only way for this to be right is if Z is even because y(odd) +z (odd) + x (even) = even number 
Then we have XYZ -> X(even)*Y(odd)*Z(odd) = EVEN
suff

christoph · Answer

C)...

1) x=2 and y=1 and z=1 YES x=4 and y=1/2 and z=3/2 NO

2) y=1 and z=3 and x=2 YES y=1/2 and z=10 and x=3/2 NO

1) and 2) x and y and z must be integers for the statements to be true

x+y+z is even, is xyz even? 1) xy even 2) yz odd

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