Chapter 14, Problem 23E

a)

To determine

To explain the approach.

Answer to Problem 23E

Probability of independent events.

Explanation of Solution

Given:

P(Once repair) = 17% = 0.17

P(Twice repair) = 7% = 0.07

P(Thrice or more) = 4% = 0.04

P(No repairs) = 0.72

P(Some repairs) = 0.28

To make the valid approach we need to assume that repairs has to be independent for the two cars.

b)

To determine

To explain whether the assumption of independence is reasonable.

Answer to Problem 23E

No.

Explanation of Solution

Given:

P(Once repair) = 17% = 0.17

P(Twice repair) = 7% = 0.07

P(Thrice or more) = 4% = 0.04

P(No repairs) = 0.72

P(Some repairs) = 0.28

To make the valid approach we need to assume that repairs has to be independent for the two cars.This assumption is likely not reasonable if a owner has more than car, then the probability of needing repairs on each of his car will not be independent. Therefore, it is also possible that two cars come in the shop as a consequence of a collision with each other, then the probability of them both needing repairs is also higher.