An insurance company reported that 50% of all automobile damage claims were made bye people under the age of 25. If seven automobile damage claims were selected at random, determine the probability that exactly five of them were made by someone under the age of 25.

Answer 1

prob(under 25) = .5
prob(not under 25) = .5

prob(exactly 5 of 7 are under 25) = C(7,5)(.5)^5 (.5)^2
= 21(.5)^7 = .....