An Oil Change Shop Claims That They Will Change Your

Essay

An oil change shop claims that they will change your oil in under 15 minutes. To test this
claim, a consumer advocacy group takes a simple random sample of 10 customers and records
the number of minutes it took to complete oil changes for these customers. Assume that oil
change times are normally distributed. $$\begin{array} { | c | } \hline \text { Minutes for Oil Change } \\\hline 8 \\\hline 2 \\\hline 7 \\\hline 12 \\\hline 14 \\\hline 11 \\\hline 25 \\\hline 8 \\\hline 43 \\\hline 15 \\\hline\end{array}$$ Conduct a hypothesis test for the oil shop's claim about oil change times at the 5% level of
significance.
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