Question

Among 8 electrical components exactly three are known to not function properly. 5 components are randomly selected, how do you find the probability that exactly two components function properly?

Answer 1

There are `((8),(5)) = 56` ways of choosing any 5 components from 8.

There are `((5),(2)) = 10` ways of choosing 2 components from the 5 good components and `((3),(3)) = 1` ways of choosing 3 components from the 3 bad components.

Therefore the odds are: `10/56 = 5/28`