Answer:
The degrees of freedom are given by:
The p value would be given by:
Since the p value is higher than 0.1 we have enough evidence to FAIl to reject the null hypothesis and we can't conclude that the true mean is less than 60
Step-by-step explanation:
Information given
60, 56, 60, 55, 70, 55, 60, and 55.
We can calculate the mean and deviation with these formulas:
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Replacing we got:
represent the mean
represent the sample standard deviation for the sample
sample size
represent the value that we want to test
represent the significance level
t would represent the statistic
represent the p value
Hypothesis to test
We want to test if the true mean is less than 60, the system of hypothesis would be:
Null hypothesis:
Alternative hypothesis:
The statistic would be given by:
(1)
Replacing the info we got:
The degrees of freedom are given by:
The p value would be given by:
Since the p value is higher than 0.1 we have enough evidence to FAIl to reject the null hypothesis and we can't conclude that the true mean is less than 60