A survey of consumers in a particular community showed that 10% were dissatisfied with plumbing jobs done in their homes. Half the complaints dealt with plumber A, who does 40% of the plumbing jobs in the town. Find the probability that a consumer will obtain a satisfactory plumbing job, given that the plumber was A.

Respuesta :

Answer: 87.5%

Step-by-step explanation:

Let say that there're 100 people in the town.

10% of population were dissatisfied with plumbing jobs => that's 10 people.

Half of them deal with Plumber A => 5 people dissatisfied with plumber A.

A does 40% of the plumbing jobs in the town => 40 people use A's service.

=> The probability that a comsumer will obtain a satisfactory plumbing job, given that the plumber was A is: (40-5)/40 = 87.5%