試題詳解

9. An insurance company examines its pool of auto insurance customers and gathers the following information:
(i) All customers insure at least one car.
(ii) 70% of the customers insure more than one car.
(iii) 20% of the customers insure a sports car.
(iv) Of those customers who insure more than one car, 15% insure a sports car.
Calculate the probability that a randomly selected customer insures exactly one car and that car is not a sports car.
(A) 0.13
(B) 0.21
(C) 0.24
(D) 0.25
(E) 0.30