The average of four consecutive numbers A, B, C, and D is 49.5. What is the product of B and D?

Let the numbers A, B, C, and D are N , N+1, N + 2 and N + 3, respectively.
According to the question,
[N + (N+1) + (N+2) + (N+3)] / 4 = 49.5
⇒ 4N + 6 = 4 x 49.5
⇒ 4N = 198 - 6 ⇒ N = 192/4
⇒ N = 48
The required product = B x D
= (N + 1) x (N + 3)
= (48 +1) (48 +3 )
= 49 x 51
= 2499