Question

A couple plans to have three children. There are eight possible arrangements of girls and boys. For example, GGB means the first two children are girls and the third child is a boy. All eight arrangements are (approximately) equally likely.

Write down all eight arrangements of the sexes of three children
Based on the eight arrangements, what is the probability of any one of these arrangements?

Answer 1

GGB

GGG

GBB

GBG

BGG

BGB

BBG

BBB

Any of these has a probability of 1:8, or 1/8, or 0.125, or 12.5%

Explanation:

GGB

GGG

GBB

GBG

BGG

BGB

BBG

BBB

Any of these has a probability of 1:8, or 1/8, or 0.125, or 12.5%