Question

A random group of thirty customers at a local theater was interviewed regarding their movie viewing habits. The following responses were obtained for the question, “How many times during the past month did you go to the movies?” Number of movies attended 0 1 2 3 4 Number of customers 3 10 8 6 3 a. b. Find the probability that a customer selected at random went to the movies:

1) more than one time, 2) two times, 3) at least two times, 4) no more than three times.

Answer 1

Number of movies attended    0        1             2              3           4              

Number of customers           3        10              8              6           3

Total number of customers = 3 + 10 + 8 + 6 + 3 = 30

(1)
P(more than 1 time) = P(2 times) + P(3 times) + P(4 times)

                             = 8/30 + 6/30 + 3/30 = 17/30 = 0.5667

(2)

P( 2 times) = 8/30 = 0.2667

(3)

P(at least 2 times) = P(2 times) + P(3 times) + P(4 times) = 8/30 + 6/30 + 3/30 = 17/30 = 0.5667

(4)
P(no more than 3 times) = P(0 times) + P(1 time) + P(2 times) + P(3 times)

                                  = 3/30   + 10/30 + 8/30 + 6/30 = 27/30 = 0.9