If x is even and b is odd, is

Question

If 'x' is even, is  x^a + y^b  = odd

1) y is not a multiple of 2

2) 'a' and 'b' are positive odd integers

Kattu404 · Answer

Given X is even, any value of a will result x(a) to be even.
So question becomes: Is y(b) even?... (Even + Even = even, we need to figure out if y(b) is even).

Statement 1: 1) y is not a multiple of 2
So, Y is basically ODD. (Y could be: 3/5/7/9). Any value of b will result to an odd value of y.
This answers the question.
So, Statement 1 is sufficient.

Statement 2: 2) 'a' and 'b' are positive odd integers
As we don't know the value of Y, we cant determined Y(b). (It could be either even or odd).
Statement 2 not sufficient.

gmattyfatty · Answer

gmatophobia  do you have the OA? I am surprised it's not A

gmatophobia · Answer

gmattyfatty  - Statement 1 states that "y is not a multiple of 2", the number can be odd or it can also be a fraction.

Ex: 1/2 is not a multiple of 2.

Also, we don't know the positive or negative nature of the powers (exponents) either in the premise or in Statement 1. All in all, statement 1 alone is not sufficient to answer the target question.

I will post the OA in some time. Meanwhile, hope this answers your concern.

deletus · Answer

we know that y is not a multiple of 2. y could be 0 thus meaning that the statement is even. y could equal 3 thus making the statement odd. therefore, A is not sufficient.

gmatophobia · Answer

Hey  deletus

A minor correction to your explanation, "  we know that y is not a multiple of 2. y could be 0 thus meaning that the statement is even  ". With respect to the condition outlined here, y cannot be 0 as zero is a multiple of 2.

P.S- Zero is a multiple of every integer.

If x is even and b is odd, is

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