Exercise 33 lists the sample space for a couple having three children. After identifying the sample space for a couple having four children, find the probability of getting three girls and one boy (in any order).

Use the given sample space or construct the required sample space to find the indicated probability.

Exercise 33

Use this sample space listing the eight simple events that are possible when a couple has three children (as in Example 2 on page 155): {bbb, bbg, bgb, bgg, gbb, gbg, ggb, ggg}. Assume that boys and girls are equally likely, so that the eight simple events are equally likely. Find the probability that when a couple has three children, there is exactly one girl.