Question

From experience, an airline knows that only 80% of the passengers booked for a certain flight actually show up. If 8 passengers are randomly selected, find the probability that fewer than 7 of them show up.

Answer 1

Here's one way to do this problem:

n = 8
p = .80
q = 1 - p = 1 - .80 = .20

You will need to find P(7) and P(8). Add those values together, then subtract from 1. This will be your probability.
You can use a binomial probability table, or calculate by hand using the following formula:

P(x) = (nCx)(p^x)[q^(n-x)]

I hope this will help.

Answer 2

Big fat tiddes