The Blair family was one of the first to come to the original 13 colonies (now part of the USA). They had 4 children. Assuming that the probability of a child being a girl is 0.5, find the probability that the Blair family had... (a) ...at least 3 girls

31.25% probability that the Blair family had at least 3 girls

Step-by-step explanation:

For each children, there are only two possible outcomes. Either it was a girl, or it was not. The probability of a child being a girl is independent of any other children. So we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.

They had 4 children.

This means that

The probability of a child being a girl is 0.5

This means that

Probability of at least 3 children:

31.25% probability that the Blair family had at least 3 girls

13664

step-by-step explanation:

=cross multiply

=100 x = 13664