The average American gets a haircut every 42 days. Is the average smaller for college students? The data below shows the results of a survey of 15 college students asking them how many days elapse between haircuts. Assume that the distribution of the population is normal.
40, 37, 42, 46, 46, 28, 31, 39, 44, 31, 45, 39, 41, 42, 48
What can be concluded at the the
α= 0.05 level of significance level of significance?
a. The test statistic= (please show your answer to 3 decimal places.)
b. The p-value = (Please show your answer to 3 decimal places.
c. Based on this, we should the null hypothesis.
Thus, the final conclusion is that ...
a.The data suggest the populaton
α= 0.05, so there is sufficient evidence to conclude that the population mean number of days between haircuts for college students is lower than 42.
b.The data suggest the population mean number of days between haircuts for college students is not significantly lower than 42 at
α= 0.05, so there is insufficient evidence to conclude that the population mean number of days between haircuts for college students is lower than 42.
c.The data suggest the population mean is not significantly lower than 42 at α= 0.05, so there is sufficient evidence to conclude that the population mean number of days between haircuts for college students is equal to 42.
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