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The Normal Distribution. AMIN SOKHANVAR 2013-12-27. Airline Passenger Loading Times.
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The Normal Distribution AMIN SOKHANVAR 2013-12-27
Airline Passenger Loading Times • After completing a study, the Chicago O’Hare Airport managers have concluded that the time needed to get passengers loaded onto an airplane is normally distributed with a mean equal to 15 minutes and a standard deviation equal to 3.5 minutes. Recently one airplane required 22 minutes to get passengers on board and ready for take off. find the probability that a flight will take 22 or more minutes to get passengers loaded.
real estate sales in Fairfax County nearWashington, D.C. • A report shows that the mean days a home stays on the market before it sells is 16 days. We assume the distribution for days on the market before a home sells is normally distributed with mean=16 and s.d=4. A local D.C. television station interviewed an individual whose home had recently sold after 14 days on the market. Find the probability that a home would require 14 or more days to sell.
GENERAL ELECTRIC COMPANY • The major problem with battery-operated cars is the limited time they can be driven before the batteries must be recharged. Suppose that General Electric (GE) has developed a Longlife battery pack it claims will power a car at a sustained speed of 45 miles per hour for an average of 8 hours. But of course there will be variations: Some battery packs will last longer and some less than 8 hours. Current data indicate that the standard deviation of battery operation time before a charge is needed is 0.4 hours. Data show a normal distribution of uptime on these battery packs. Automakers are concerned that batteries may run short. For example, drivers might find an “8-hour” battery that lasts 7.5 hours or less unacceptable. What are the chances of this happening with the Longlife battery pack?