Question: Find the probability a couple with 5 children have no more than 2 girls.

Solution: Using the counting principle, we have that

p(X is no more than 2 girls) = p (X =0 girls) + p(X = 1 girl) + p(X = 2 girl)

A student club consists of 12 guys and 10 girls. A committee of 8 is to be selected. In how many ways can this be done if

12.) the committee must have the same number of guys as girls

13.) four officers (president, vice president, treasure and secretary) are selected from ALL 22 members.