# Normal Probability Distribution

The goal at U.S. airports handling international flights is to clear these flights within 45 minutes. Let's interpret this to mean that 95 percent of the flights are cleared in 45 minutes, so 5 percent of the flights take longer to clear. Let's also assume that the distribution is approximately normal.

a) If the standard deviation of the time to clear an international flight is 5 minutes, what is the mean time to clear a flight?

b)Suppose the standard deviation is 10 minutes, not the 5 minutes suggest in part a) what is the mean?

c) A customer has 30 minutes from the time her flight landed to catch her limousine. Assuming a standard deviation of 10 minutes, what is the likelihood that she will be cleared in time?

https://brainmass.com/statistics/probability/33600

#### Solution Preview

a) If the standard deviation of the time to clear an international flight is 5 minutes, what is the mean time to clear a flight?

M +z*s=45minutes

where M = mean and

z coreesponds to 95%confidence 1 tailed test

or 5.00%level of significance (a (alpha) =0.05)

This is a 1 tailed test because we have the condition that 5 percent of the flights take longer to clear

95 percent of the flights are cleared in 45 minutes, so 5 ...

#### Solution Summary

Answer to questions on Normal Probability Distribution. It calculates the mean time to clear a flight.