SOLUTION: The recommended number of hours of sleep per night is 8 hours, but everybody "knows" that the average college student sleeps less than 7 hours. The number of hours slept last night

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Question 856514: The recommended number of hours of sleep per night is 8 hours, but everybody "knows" that the average college student sleeps less than 7 hours. The number of hours slept last night by 10 randomly selected college students is listed below. Complete the following hypothesis test: Ho: μ = 7, Ha: μ < 7, α = 0.05.

6.1
6
6.3
6.6
7.7
7.7
7.8
6.3
6.4
6.2

(a) Find t. (Give your answer correct to two decimal places.)
(this is what I answered but it was counted wrong) -12.91 .
(ii) Find the p-value. (Give your answer correct to four decimal places.)

Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website!
what did You get for sample mean and use for standard deviation?
re Reply:

Hi,
Yes, mean = 6.71
x x - 6.71 (x-6.71)^2
6.1 -0.61 0.3721
6 -0.71 0.5041
6.3 -0.41 0.1681
6.6 -0.11 0.0121
7.7 0.99 0.9801
7.7 0.99 0.9801
7.8 1.09 1.1881
6.3 -0.41 0.1681
6.4 -0.31 0.0961
6.2 -0.51 0.2601
sum 67.1 4.729
sum/10 6.71 sum/9 0.525444444
sqrt(sum/9) 0.724875468
Sample SD = .725
a) t =
ii) p-value = NORMSDIST(-1.2664) = .1027>.05 Sample does NOT show mean is <7