Question: is 20 odd or even?
Answer: Even numbers always end with a digit of 0, 2, 4, 6 or 8. 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30 are even numbers. Odd numbers always end with a digit of 1, 3, 5, 7, or 9.