11 Acme Airlines flies airplanes that seat 12 passengers Fro

11. Acme Airlines flies airplanes that seat 12 passengers. From experience, they have learned that, on average, 80% of the passengers holding reservations for a particular flight actually show up for the flight. If they book 13 passengers for a flight, what is the probability that 12 or fewer passengers holding reservations will actually show up for the flight? (Write a, b, or c as your answer.) less than 90% between 90 and 95%, inclusive more than 95%

Solution

Using a cumulative binomial distribution table or technology, matching          
          
n = number of trials =    13      
p = the probability of a success =    0.8      
x = the maximum number of successes =    12      
          
Then the cumulative probability is          
          
P(at most   12   ) =    0.945024419
          
Thus, it is

OPTION B: BETWEEN 90 AND 95%, INCLUSIVE [ANSWER]