Prove that the sum of two consecutive odd numbers is divisible by 4.

Let two consecutive odd numbers be (2n + 1) and (2n + 3) for some integer n. Sum = (2n + 1) + (2n + 3) = 4n + 4 = 4(n + 1). On dividing the sum by 4, we get : = n + 1. Hence, proved that sum of two consecutive odd numbers is divisible by 4.