Lets say C stands for done by contractor, and F stands for done by the firm itself. N stands for negative (complained calls), and P stands for positive (uncomplained calls). Thus, NsubC is complained contractor calls, NsubF is complained firm calls, PsubC is uncomplained contractor calls, and PsubF is uncomplained firm calls.
Total contractor calls = 85% = PsubC + NsubC = (1)*85% = (90% + 10%)*85%
NsubC = 10%*85% = (1/10)*85% = 8.50%
Total firm calls = 15% = PsubF + NsubF = (1)*15% = (95% + 5%)*15%
NsubF = 5%*15% = (1/20)*15% = 0.75%
N = NsubC + NsubF = 8.50% + 0.75% = 9.25%
∴
a.) N = 9.25%
b.) NsubC = 8.50%
A large firm has 85% of its service calls made by a contractor, and 10% of these calls
result in customer complaints. The other 15% of the service calls are made by their
own employees, and these calls have a 5% complaint rate. Find the
(a) probability of receiving a complaint.
(b) probability that the complaint was from a customer serviced by the
contractor.
1 answer
1 answer