David's gasoline station offers 4 cents off per litre if the customer pays in cash and does not use a credit card. Past evidence indicates that 40% of all customers pay in cash. During a one-hour period twenty-five customers buy gasoline at this station. What is the probability that at least ten pay in cash?
A) 0.416
B) 0.575
C) 0.586
D) 0.425

Question

Quizplus · Accepted Answer

We can use the binomial distribution formula to solve the problem. Let X be the number of customers who pay in cash. Then X follows a binomial distribution with n = 25 (total number of customers) and p = 0.4 (probability that a customer pays in cash). We want to find P(X >= 10).

Using a calculator or software, we can find P(X >= 10) = 0.575. Therefore, the best choice is B.

David's Gasoline Station Offers 4 Cents Off Per Litre If