A community of 100 homes constructed in 2009 contains 47 that used conventional construction. The reminder used Energy Star building standards. A real estate agent is going to show a client 5 homes. What is the probability that 3 were built using conventional methods?
prob of conventual home = 47/100
prob of ES = 53/100
prob(3 of 5 to be conventinal
= C(5,3)(47/100)^3 (53/100)^2
= .2916