## Elementary Statistics (12th Edition)

$H_{0}:\mu_d=0,$ $H_{a}:\mu_d\ne0$. The test statistic is:$t=\frac{\overline{d}-\mu_d}{s_d/\sqrt{n}}=\frac{-72.2-0}{9.3113/\sqrt{5}}=-17.339.$ The P is the corresponding probability using the table with df=5-1=4, hence P is less than 0.01. If the P-value is less than $\alpha$, which is the significance level, then this means the rejection of the null hypothesis. Hence:P is lessthan $\alpha=0.01$, hence we reject the null hypothesis. Hence the measurements from the two arms seem to be a bit different.