Problem
Complete the table below. High Temperatures $\left({ }^{\circ} \mathrm{F}\right) \quad$ (Round to the nearest hundredth as needed.) \begin{tabular}{|l|c|c|c|c|} \hline Class & Frequency, $\mathrm{f}$ & Midpoint & \begin{tabular}{l} Relative \\ frequency \end{tabular} & \begin{tabular}{l} Cumulative \\ frequency \end{tabular} \\ \hline $18-28$ & 17 & 23 & 0.05 & 17 \\ \hline $29-39$ & 42 & 34 & 0.12 & 59 \\ \hline $40-50$ & 68 & 45.0 & 0.19 & 127 \\ $51-61$ & 69 & $\square$ & $\square$ & $\square$ \\ \hline \end{tabular}
Solution
Step 1 ：Calculate the midpoint for the class 51-61 by taking the average of the lower and upper bounds of the class. This gives us \(\frac{51+61}{2} = 56.0\).
Step 2 ：Calculate the relative frequency for the class 51-61 by dividing the frequency of the class by the total frequency of all classes. This gives us \(\frac{69}{196} = 0.3520408163265306\). Round this to the nearest hundredth to get 0.35.
Step 3 ：Calculate the cumulative frequency for the class 51-61 by adding the frequencies of the current class and all previous classes. This gives us \(17 + 42 + 68 + 69 = 196\).
Step 4 ：The midpoint for the class 51-61 is \(\boxed{56.0}\), the relative frequency is \(\boxed{0.35}\), and the cumulative frequency is \(\boxed{196}\).
