A company surveyed 2,600 North American airline passengers and reported that approximately 75% said that they carry a smartphone when they travel. Suppose that the actual percentage is 75%. Consider randomly selecting ten passengers and define the random variable x to be the number of the ten selected passengers who travel with a smartphone. The probability distribution of x is the binomial distribution with
n = 10
and
p = 0.75.
(Round your answers to three decimal places.)
(a)
Calculate p(9).
p(9) =
0.188
(b)
Calculate P(x ≤ 7).
P(x ≤ 7) =
(c)
Calculate the probability that more than half of the selected passengers travel with a smartphone.