All families of six children in a large city were surveyed I

All families of six children in a large city were surveyed. In 36 families, the exact order of births of boys and girls was G B G B B G. What is your estimate of the number of families in which the exact order of births was B G B G B G?

Solution

As the probability of any order of gender is just the same (as births genders are independent of each other), then there must be about the same GBGBBG as BGBGBG.

Thus, we estimate that there are also 36 BGBGBG families. [ANSWER, 36]