Captive primates, such as monkeys, often experience fractured bones. The probability distribution from a study of the X- rays of 500 captive spider monkeys shows that fifteen percent of them had one healed fracture; twenty percent had two healed fractures; twenty-five percent had three healed fractures; and forty percent had four healed fractures. About how many healed fractures would you expect a randomly selected captive spider monkey to have based on this probability distribution?