a charter airline packs customers in It will take 80 passeng

a charter airline packs customers in. It will take 80 passengers. The safe payload for the passengers is 16,000 pounds. On a full flight, this is an average of 200 pounds per passenger. Assuming passengers are selected at random from a population with mean of 180 pounds and standard deviation of 40 pounds, how often will 80 passengers overload the plane?