Discuss the below:
The length of time to do a complete full service oil change at Speedy-Lube is normally distributed with a mean of 15.8 minutes and a standard deviation of 2.2 minutes.
Q: What percentage of complete full service oil changes will take less than 10 minutes? If 1000 cars had a complete full service oil change, how many would you expect to be finished in more than 20 minutes?