Answer:
Yes. There are easy rules to follow for this:
even + even always equals even
odd + odd always equals even
even + odd always equals odd
Lets try examples:
1) even + even: 6 + 6 = 12, 4+2 = 6, 12+ 8 = 20, etc
2) odd + odd: 7 + 7 = 14, 5+3 = 8, 17 + 1 = 18, etc
3) even + odd: 7 + 6 = 13, 3+4 = 7, 13 + 6 = 19, etc
Hope this helps!