Two digits are selected at random from the digits 1 through 9. If their sum is even, then the probability that both are odd is

Step-by-step solution

Let A= Getting two odd numbers B= Getting the sum as an even number. Required probability P(A / B)= P(A B) P(B) P(A / B)= ^5 C₂ ^9 C₂ ^4 C₂+ ^5 C₂ ^9 C₂ = 5 8