Environmental inspector decides to examine the exhaust of 6

Environmental inspector decides to examine the exhaust of 6 of 24 trucks. If 4 of the 24 trucks emit excessive amounts of pollutants and would fail the inspection. What is the probability that all of the 6 inspected pass the inspection?

Solution

20C6/24C6

As 4 of 24 fail the test only 20 among 24 exhaust less pollutants.

probabilty of choosing 6 ut of 20 is 20C6/24C6