Assume that travel time by car between Buffalo and Rochester

Assume that travel time (by car) between Buffalo and Rochester follows a normal distribution with mean of 80 minutes and standard deviation of 15 minutes. Distance between Buffalo and Rochester is 80 miles. How fast do you need to drive (driving at constant speed without stopping) in order to arrive in top 10% of the fastest drivers? Solve the same problem, but assume lognormal distribution for travel time. Maximum allowed speed is 65 miles per hour. What is the percent (fraction) of the drivers who drive faster than it is allowed? For this part, you can assume normal distribution and that drivers are driving at constant speed with no stopping.

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