Question

Two dice were thrown and it is known that the numbers which come up were different. Find the probability that the sum of the two numbers was 5. Select the correct answer from above options

Answer 1

Correct Answer - `2/15` Let A = event that the sum of two numbers appeared is 5, and B = event that the two dice show different numbers. The, `A={(2, 3), (3, 2), (1, 4), (4, 1)}`. Thus, `n(A)=4, n(B)=30, A nn B=A` and so `n(A nn B)=n(A)=4`. `:.` the required probability `=P(A//B)=(n (A nn B))/(n(B))=4/30=2/15`.