Question

A Snapshot in USA Today indicates that 51% of Americans say the average person is not very considerate of others when talking on a cellphone.

Suppose that 100 Americans are randomly selected.

Find the approximate probability that 64 or more Americans would indicate that the average person is not very considerate of others when talking on a cellphone.

Answer 1

0.00411

Explanation:

Given that a snap shot in USA Today indicates that 51% of Americans say the average person is not very considerate of others when talking on a cellphone.

Sample size n = 100

Sample proportion p is Normal with mean = 0.51 and variance =
`(pq)/(n) \\=(0.51(0.49))/(100) \\=0.002419\\`

std dev = 0.049183

the approximate probability that 64 or more Americans would indicate that the average person is not very considerate of others when talking on a cellphone.

=
`P(p\geq 0.64)=\\P(Z\geq (0.64-0.51)/(0.049183) )\\\\=P(Z\geq 0.643)\\=0.00411`