if x,y and z are integers, is x(y^2 + z^3) even ?
(1) x is odd
(2) xyz is odd
OA is B , but I got C
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if x,y and z are integers, is x(y^2 + z^3) even ?
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scoobydooby
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is x(y^2 + z^3) even ?
stmt 1) x is odd
case 1: y and z even=>O(E+E)=E
case 2: y and z odd=> O(O+O)=O*E=E
case 3: x even, y odd or vice versa=> O(O+E)=O*O=O
not sufficient
stmt 2) xyz is odd
=> x, y and z all are odd (if any one was even then xyz would have been even)
O(O+O)=O*E=E
sufficient
hence B
stmt 1) x is odd
case 1: y and z even=>O(E+E)=E
case 2: y and z odd=> O(O+O)=O*E=E
case 3: x even, y odd or vice versa=> O(O+E)=O*O=O
not sufficient
stmt 2) xyz is odd
=> x, y and z all are odd (if any one was even then xyz would have been even)
O(O+O)=O*E=E
sufficient
hence B
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sanjay_dce
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goelmohit2002
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if any of x, y or z are even, then the product xyz cannot be odd....quocbao wrote:Can you explain why x,y,z is odd from statement 2 ?
We can also have x is odd, y z is even also ?
