SOLUTION: According to the Sleep Foundation, the average night's sleep is 6.8 hours (Fortune, March 20, 2006). Assume the standard deviation is .7 hours and that the probability distribution

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Question 465440: According to the Sleep Foundation, the average night's sleep is 6.8 hours (Fortune, March 20, 2006). Assume the standard deviation is .7 hours and that the probability distribution is normal.
What is the probability that a randomly selected person sleeps more than 8 hours (to 4 decimals)?

What is the probability that a randomly selected person sleeps 6 hours or less (to 4 decimals)?

Doctors suggest getting between 7 and 9 hours of sleep each night. What percentage of the population gets this much sleep (to the nearest whole number)?
%
Answer by edjones(8007) (Show Source):
You can put this solution on YOUR website!
z=(8-6.8)/.7=1.714
Area under normal curve above 1.714 is .0433 the probability that a randomly selected person sleeps more than 8 hours.
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Ed