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pls help guys...

If y is not equal to 3 and 2x/y is a prime integer greater than 2, which of the following must be true?

I. x = y
II. y = 1
III. x and y are prime integers.

(A) None

( I only

(C) II only

(D) III only

(E) I and II

thanx...

Hey Naaz,

Could not understand the question. How is y related to 3? The information did not come properly.

Also 2 x/y could not be a prime integer greater than 2. The only even integer thats prime is 2. Also anything multiplied by even will always be even. So 2x/y cannot be a prime integer greater than 2 as the result will always be even.

Could you elucidate the question once more?

Thanks,
Rahul.

rchuck21 wrote:
Hey Naaz,

Could not understand the question. How is y related to 3? The information did not come properly.

Also 2 x/y could not be a prime integer greater than 2. The only even integer thats prime is 2. Also anything multiplied by even will always be even. So 2x/y cannot be a prime integer greater than 2 as the result will always be even.

Could you elucidate the question once more?

Thanks,
Rahul.

hey rahul...sorry for the typo error..have corrected it now...could u help me with this sum pls?

Thanks Naaz,

As I have said before if x/y is an integer, whatever the value it would have, the result is always even as it is multiplied by 2.

Now since 2x/y is a prime integer greater than 2, then it has to be an odd number as all prime numbers except 2 are odd. Only way that could happen is that you have to cancel out 2. That could only happen if x/y is a fraction where y is always 2. Since y is always 2, it would cancel out 2 in 2x/y with only x remaining.

So x can be any prime number except 2 for 2x/y being a prime number greater than 2 to hold true.

For eg x/y can be 3/2 or 5/2 or 7/2 ......... but the condition is y always has to be 2.

So only statement C is correct which says that x& y are prime integers where y =2 and x be any other prime integer greater than 2.

Answer is (D)

Sorry for the information before that 2x/y can never be a prime integer greater than 2. This will hold true if x/y is an integer. But with x/y as fraction, we have just seen that 2x/y can be a prime integer greater than 2. Just have to cancel out 2.

Hope the answer is OK and I was able to explain my views to you properly.

Thanks for the questions.

Cheers,
Rahul.

rchuck21 wrote:
Sorry for the information before that 2x/y can never be a prime integer greater than 2. This will hold true if x/y is an integer. But with x/y as fraction, we have just seen that 2x/y can be a prime integer greater than 2. Just have to cancel out 2.

Hope the answer is OK and I was able to explain my views to you properly.

Thanks for the questions.

Cheers,
Rahul.

hey rahul...u fell for the trap..try again...Ans D is not correct...will post up the soln late evening..

cheers,

Bhavin