Question

The sum of an odd number and and enven number is always even

Answer 1

let \(a\) be even and \(b\) be odd.
\(a=2k\) for some \(k\in \mathbb{Z}\) and \(b=2k_0+1\) for some \(k_0\in \mathbb{Z}\)
\(a+b=2k+2k_0+1=2(k+k_0)+1\)
Thus \(a+b\) is always odd.

Answer 2

you can just answer NO with any counter example

1+0 = 1

1 is odd, 0 is even....

Answer 3

@nikki_here understand?