(0 + odd number) + (0 + even number)
odd number = 1
even number = 2
(0 + 1) + (0 + 2) = ?
1 + 2 = ?
3
odd number = 3
even number = 2
3 + 2 = 5
5
1ODD + 1EVEN = AN ODD NUMBER
So basically:
E + O = Odd
O + E = Odd
E + E = Even
O + O = Even
It also applies in multiplication:
(-)(+) = -
(+)(-) = -
+ * + = +
- * - = +
