If x and y are integers whose product is 900, then which of

Question

If x and y are integers whose product is 900, then which of the following must be true?

 X-Y > 0

 X=Y

 Either x or y is divisible by 10. 
 
 If x is even, then y is even. 
 
 If x is odd, then y is even.

v1rok · Answer

The last condition must be true:

If x is odd, then y is even.

Easy to see after decomposing 900 into prime numbers

gmatcrook · Answer

answer is E.

900 = 2 x 2 x 3 x 5 x 3 x 5

If X is any of the odd mulitple, 3, 5, 15 etc then the rest of the number will form up a multiple with 2.

Thus, if X is odd then the other number has to be even.

haas_mba07 · Answer

E. If x is odd, then y is even

By PoE, only E survives.

u2lover · Answer

was b/w C and E... but C says either must be divisible, yet both can be divisible

2 combinations I used -100 & -9 and 30 & 30

so my answer is E

agsfaltex · Answer

You folks are really sharp! OA is E,

I got confused between C and E, but u2lover is right, BOTH x and y can be divisible by 10, but C says only one is!

ps_dahiya · Answer

It may be possible that none of them is divisible by 10. Consider x = 4 and y = 225

Answer should be E.

If x and y are integers whose product is 900, then which of

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