Question

Find the complement of the event: Having all girls in a family with three children. (Do not count parents.) and Find the complement of the event: Having exactly 1 boy in a family with three children. (Do not count parents.)

Answer 1

Complement of an event is all the other outcomes (not the ones we want).

1) The complement of having all girls in family with 3 children is having no girl in family with 3 children.

I.e. having all boys in family with 3 children.

2)

The complement of exactly one boy with 3 childern in family is either none is boy or more than one boy.

I.e there are none boy or 2 boys or 3 boys with 3 children family.