Prime

[MBA.Aspirant]

If
(x + 5)/y
is a prime integer, which of the following must be true?
I. y = 5x
II. y is a prime integer.
III.(x + 5)/y is odd.
(A) None
(B) I only
(C) II only
(D) I and II only
(E) II and III only

[Anurag@Gurome]

If (x + 5)/y is a prime integer, which of the following must be true?
I. y = 5x
II. y is a prime integer.
III.(x + 5)/y is odd.

Let x = 3 and y = 4, then (x + 5)/y = (3 + 5)/4 = 2 --> A prime integer

But neither y = 5x nor y is prime integer nor (x + 5)/y is odd.
Hence, all of them are false.

The correct answer is A.

[cans]

(x+5)/y is prime
a)y=5x. not true. (x=4,y=3)
b)y is prime. not true. x=3,y=4
c)(x+5)/y is odd. not true. x=3,y=4
IMO A

[MBA.Aspirant]

Thanks Dr. Anurag

[sunilramu]

(x + 5)/y
is a prime integer, which of the following must be true?
I. y = 5x
II. y is a prime integer.
III.(x + 5)/y is odd.

(x+5) = y.P where P is a prime.
Select values for x and y such that P is 2
(x+5)=2y
y=1 => x=-3 will negate I, II and III

IMO A

[Ahmed MS]

I am wondering if we take the value of x=4, and value of y=3, then option ii and iii will be right. As (x+5)/y, will be the prime integer.

So, (4+5)/3 = 9/3 = 3


Pardon me if I am wrong.


Cheers.

[cans]

I am wondering if we take the value of x=4, and value of y=3, then option ii and iii will be right. As (x+5)/y, will be the prime integer.

So, (4+5)/3 = 9/3 = 3


Pardon me if I am wrong.


Cheers.

If
(x + 5)/y
is a prime integer, which of the following must be true?

Question says must be true. Thus it should be true for all values of x and y. and not just one pair.

[sandeep800]

A is correct...

[MBA.Aspirant]

I am wondering if we take the value of x=4, and value of y=3, then option ii and iii will be right. As (x+5)/y, will be the prime integer.

So, (4+5)/3 = 9/3 = 3


Pardon me if I am wrong.


Cheers.

If
(x + 5)/y
is a prime integer, which of the following must be true?

Question says must be true. Thus it should be true for all values of x and y. and not just one pair.

@ Cans: when x=4 y =3, II and III will be true

x+5/y = 4+5/3 = 3 <= prime integer

II) y is a prime integer.
III.(x + 5)/y is odd.

??

[cans]

I am wondering if we take the value of x=4, and value of y=3, then option ii and iii will be right. As (x+5)/y, will be the prime integer.

So, (4+5)/3 = 9/3 = 3


Pardon me if I am wrong.


Cheers.

If
(x + 5)/y
is a prime integer, which of the following must be true?

Question says must be true. Thus it should be true for all values of x and y. and not just one pair.

@ Cans: when x=4 y =3, II and III will be true

x+5/y = 4+5/3 = 3 <= prime integer

II) y is a prime integer.
III.(x + 5)/y is odd.

??

Yeah when x=4,y=3 II and III will be true.
But the question says

which of the following must be true?

Thus they ought to be true for all value of x and y and not just for x=4,y=3.
Say x=1,y=1, y is not prime and (x+5)/y is not odd. Thus we choose 'A'. None