The number of hours adults sleep per night is normally distributed with a mean of 7.3...
The number of hours of sleep in a night is normally distributed in adults, with a mean of 7.2 hours and a standard deviation of 1.7 hours. Suppose a randomly selected adult sleeps 7.3 hours in a night. What percentile are they - that is, what percentage of adults do they sleep more than?
The number of hours of sleep each student gets per night is approximately normally distributed with mean of 7 hours and standard deviation of 1.25 hours. (c) Cognitive functioning drops off dramatically without enough sleep. Suppose that Health Services wants to help the students who sleep the least. Due to budget constraints, they will focus their efforts on students who are in the bottom 5% of hours slept. At what number of hours should they focus their efforts?
The number of sleep hours for adults is normally distributed with mean 7 hours and standard deviation 1.7 hours. How large a sample should be selected if we we wish our estimate to be correct within 30 minutes with 95% confidence? a) 44 b)45 c)12 d)11
the amount of sleep per night of us.adults follows a normal distribution with mean 7.5 hours and A lot of research is conducted on the sleeping habits of US adults. One study reported that standard de 12 hours Question 1 1 The shaded area in the image below represents which of the follow n PXX-5 PSX9.5) PEX- S X 9.5) PX X5 Question 14 of 18 Using the Standard Deviation Rule, what is the probability that a randomly chosen U.S....
The distribution of hours of sleep per week night, among college students, is found to be Normally distributed, with a mean of 6.5 hours and a standard deviation of 1 hour. What range contains the middle 95% of hours slept per week night by college students (a) 5.5 and 7.5 hours per week night (b) 4.5 and 7.5 hours per week night (c) 4.5 and 8.5 hours per week night 3.19
It is recommended that adults get 8 hours of sleep each night. A researcher hypothesized college students got less than the recommended number of hours of sleep each night, on average. The researcher randomly sampled 20 college students and calculated a sample mean of 7.5 hours per night. If the researcher wanted to perform a one-sample t-test, which of the following is a correct statement? Choose the correct answer below. A. The distribution of sample means will be normal even...
Based on a random sample of 1040 adults, the mean amount of sleep per night is 8.37 hours. Assuming the population standard deviation for amount of sleep per night is 2.7 hours, construct and interpret a 95% confidence interval for the mean amount of sleep per night. A 95% confidence interval is (DD (Round to two decimal places as needed.)
Based on a random sample of 1160 adults, the mean amount of sleep per night is 8.49 hours. Assuming the population standard deviation for amount of sleep per night is 3.6 hours, construct and interpret a 95% confidence interval for the mean amount of sleep per night. A 95% confidence interval is (_____,_______). (Round to two decimal places as needed.)
Based on a random sample of 1080 adults, the mean amount of sleep per night is 8.41 hours. Assuming the population standard deviation for amount of sleep per night is 3.8hours, construct and interpret a 90% confidence interval for the mean amount of sleep per night. A 90% confidence interval is (nothing,nothing). (Round to two decimal places as needed.)
College students average 7.8 hours of sleep per night with a standard deviation of 45 minutes. If the amount of sleep is normally distributed, what proportion of college students sleep for more than 9 hours?