Posted by **Mia** on Tuesday, May 6, 2014 at 11:47am.

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.

a. What is the probability that a randomly selected person sleeps more than 8 hours (to 4 decimals)?

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

c. 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 This Question

## Related Questions

- Economics (37) - According to the Sleep Foundation, the average night's sleep is...
- statistics - researchers believe a new sleep on average 10 hours per night...
- statistics - A 4 to 7 month old baby sleeps an average of 14 hours per day. At ...
- statistics - A 4 to 7 month old baby sleeps an average of 14 hours per day. At ...
- statistics - The number of hours that college students sleep on a week night is...
- Probability/Statistics - Using diaries for many weeks, a study on the lifestyles...
- statistics - College students average 7.8 hours of sleep per night with a ...
- Statistics - the average numbers of hours a cat sleep is approximately normally...
- Statistics - Suppose that hours of sleep per night for single adults between 30 ...
- statistics - The typical amount of sleep per night for undergraduate college ...

More Related Questions