Suppose that 5% of cereal boxes contain a prize and the other 95% contain the message,

Question:

Suppose that 5% of cereal boxes contain a prize and the other 95% contain the message, “ Sorry, try again.” Consider the random variable x, where x = number of boxes purchased until a prize is found.
a. What is the probability that at most two boxes must be purchased?
b. What is the probability that exactly four boxes must be purchased?
c. What is the probability that more than four boxes must be purchased?