9.2 Exercise 24

Glenn makes five sales calls, with probabilities $0.37$, $0.52$, $0.48$, $0.71$, $0.63$, of success on the respective calls. Margaret makes four sales calls with probabilities $0.77$, $0.82$, $0.75$, $0.91$, of success on the respective calls. Assume that all nine events form an independent class. If Glenn realizes a profit of $18.00 on each sale and Margaret earns $20.00 on each sale, what is the probability Margaret's gain is at least $10.00 more than Glenn's?