A pair of fair dice is rolled and the sum of the numbers is noted. Determine the probability that one die resulted in a 5 given that the sum is 8.

Pairs whose sum is 8:

2 + 6, 3 + 5, 4 + 4, 5 + 3, 6 + 2 (there are 5 pairs)

Pairs when one die is 5: 3 + 5, 5 + 3 (2 pairs)

P (A) = 2 / 5 = 0.4

Answer: The probability that one die resulted in a 5 given that a sum is 8 is 0.4.