x could be 15 and y could be 9 and then 3x/y = (3 x 15)/9 = 5 which is prime number.
Therefore answer A is correct. None of the results is essentially true.
Cheers!!!
Which of the following must be true?
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If 3x/y = 5, then 3x=5y.Which must be true?
I) x=y
II) y=1
III) x and y are prime integers
In this case, it's possible that x=10 and y=6.
Thus, none of the options must be true.
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Hi phanikpk,
When a GMAT Quant question asks "which of the following MUST be true?", the way to interpret this question is in the following manner:
"...which of the following is ALWAYS TRUE, NO MATTER HOW MANY DIFFERENT VARIATIONS YOU CAN THINK OF?" By definition, this will require a higher level of thinking on your part and likely a bit more work.
You did enough work to prove that X=Y COULD be true, but with a bit more work, you would have proved that it ISN'T ALWAYS true.
GMAT assassins aren't born, they're made,
Rich
When a GMAT Quant question asks "which of the following MUST be true?", the way to interpret this question is in the following manner:
"...which of the following is ALWAYS TRUE, NO MATTER HOW MANY DIFFERENT VARIATIONS YOU CAN THINK OF?" By definition, this will require a higher level of thinking on your part and likely a bit more work.
You did enough work to prove that X=Y COULD be true, but with a bit more work, you would have proved that it ISN'T ALWAYS true.
GMAT assassins aren't born, they're made,
Rich
