posted by Joy on .
The probability that a person has an unlisted telephone number is 0.15. The district manager of
a political action group is phoning people urging them to vote. In a district with 416 households, all households have phones. What is the probability that the district manger will find that:
(a) 50 or fewer households in the district will have unlisted numbers?
(a) 345 or more have listed phone numbers?
(c) between 40 and 80 have unlisted numbers?