If m is a positive integer and m = x + y + 2z, is m odd ?

Question

(1) x and y are consecutive positive integers.
(2) 4z is even.

Are You Up For the Challenge: 700 Level Questions

Leadership · Answer

m - positive
m = x + y + 2z .... 
Pre-calculating: we are sure that 2z is even. If anyone from X or Y is odd then, m will be odd. If both are odd/even, then m will be even.

Statement 1:  - x and y are consecutive pos. int - take example of 1&2, 2&3 ... the sum will be always ODD - Sufficient

A D /  B C E

Statement 2:  - 4z is even. We already know z does not have an importance to find whether m is odd or even. Hence, insufficient

'A' is the winner

ShankSouljaBoi · Answer

Z is integer or postive or negative not been given.

1----z = 2 m = odd
z = -1/2 m = even

2. insuff
combined
z= -3/2 m = even
z= 2 m = odd

E

cjcalero24 · Answer

Statement 1: 
  
Tells us that x+y is odd because if x and y are consecutive integers they can be rewritten as 2x+1

From here its still not sufficient because we don't know if z is an integer or not. For example if z is an integer then m is odd but if z =1/2 then 2x= 1 and m is even

Not Sufficient

Statement 2:
  
Not sufficient, no new information. For the purposes of this question there is no difference in 2z and 4z they both result in an even if z is an integer and can be odd if z is not an integer

Statements 1 & 2: 
  
Not sufficient because we don't know if z is an integer or not.

E

If m is a positive integer and m = x + y + 2z, is m odd ?

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