At a convenience store there is a 25% chance a customer enters the store within one minute of closing time. Describe the complementary event and find its probability.

By definition: "Complementary events are two outcomes of an event that are the only two possible outcomes"

There are two (2) outcomes in this event. A customer entering the store 1 minute before closing, and a costumer NOT entering a store 1 minute before leaving.

a) The complementary event is costumer NOT entering a store 1 minute before leaving.

b) The probability is 75% chance of a costumer NOT entering the store 1 minute before closing.