Two numbers are selected at random from integers 1 through 9 If the sum is even, find the probability that both the numbers are odd.

Given: Two numbers are selected at random from integers 1 to 9.


Let A be the event when both the numbers are odd.


A = {(3, 1), (5, 1), (7, 1), (9, 1), (3, 5), (3, 7), (3, 9), (5, 3), (5, 7), (5, 9), (7, 3), (7, 5), (7, 9), (9, 3), (9, 5), (9, 7)}


Let B be the event when sum of both numbers is even.


B = {(1, 3(, (1, 5), (2, 4), (1, 7), (2, 6), (3, 5), (1, 9), (2, 8), (3, 7), (4, 6), (7, 5), (8, 4), (9, 3), (8, 6), (9, 5), (9, 7)}


A B = {(1, 3), (1, 5), (1, 7), (3, 5), (1, 9), (3, 7), (7, 5), (9, 3), (9, 5), (9, 7)}




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