1 .
When a couple has a child, this child is a boy with probability 1/2 and a girl with probability 1/2,
independent of the gender of the other children. A couple stops having children as soon as they have
2 girls or 2 boys. Consider the random variables
- G = the number of girls the couple has,
and
- B = the number of boys the couple has.
Which of the following is correct?