The mean of a binomial probability distribution is given by μ = np where n is the number of trials (number of samples) and p is the probability of success.
Given that a statistics class at wilmington college has 25 students of which 15 are math majors and 10 are business majors and selecting a business major is defined as a success.
p = 10 / 25 = 0.4
If the professor randomly selects five students to work together on a group project, the mean of this probability distribution is given by 5 x 0.4 = 2.