Gre.al.13 sum of even and odd numbers

[karush]

$\tiny{gre.al.13}$
For which of the following conditions will the sum of integers m and n always be an odd integer.?
a. m is an odd integer
b. n is an odd integer
c. m and n both are odd integers
d. m and n both are even integers
e. m is an odd integer and n is an even integerI chose e just playing with numbers
don't know the exact theory on this

 

[topsquark]

Say m and n are even. Then we can say that m = 2p and n = 2q. So m + n = 2p + 2q = 2(p + q), which is even.

Say m is odd and n is odd. Then we can say m = 2p + 1 and n = 2q + 1. Etc.

-Dan

 

[karush]

got it

never liked number theorem questions