試題詳解

10. The on-line access computer service industry is growing at an extraordinary rate. Current estimates suggest that only 20% of the home-based computers have access to on-line services. This number is expected to grow quickly over the next five years. Suppose 25 people with home-based computers were randomly and independently sampled.Find the probability that fewer than half of those sampled currently have access to on-line service.
(A) 1,000
(B) .998
(C)994
(D).999