Using the given frequency distribution table, find the grouped mean. Frequency Distribution of 25 Test Scores
$$\begin{array} { | c | c | c | c | }
\hline \begin{array} { c }
\text { Class } \
\text { Interval }
\end{array} & \text { Midpoint } & \text { lally } & \begin{array} { c }
\text { Class } \
\text { Frequency }
\end{array} \
\hline 45 - 49 & 47 & / & 1 \
\hline 50 - 54 & 52 & / & 1 \
\hline 55 - 59 & 57 & / / & 2 \
\hline 60 - 64 & 62 & / & 1 \
\hline 65 - 69 & 67 & / & 1 \
\hline 70 - 74 & 72 & / / & 2 \
\hline 75 - 79 & 77 & / / / & 3 \
\hline 80 - 84 & 82 & / / / & 3 \
\hline 85 - 89 & 87 & / / / & 3 \
\hline 90 - 94 & 92 & / / / / / & 5 \
\hline 95 - 99 & 97 & / / / & 3 \
\hline
\end{array}$$
A)1,975
B)79
C)180
D)72

Question

Using the given frequency distribution table, find the grouped mean. Frequency Distribution of 25 Test Scores
$$\begin{array} { | c | c | c | c | } 
\hline \begin{array} { c } 
\text { Class } \
\text { Interval }
\end{array} & \text { Midpoint } & \text { lally } & \begin{array} { c } 
\text { Class } \
\text { Frequency }
\end{array} \
\hline 45 - 49 & 47 & / & 1 \
\hline 50 - 54 & 52 & / & 1 \
\hline 55 - 59 & 57 & / / & 2 \
\hline 60 - 64 & 62 & / & 1 \
\hline 65 - 69 & 67 & / & 1 \
\hline 70 - 74 & 72 & / / & 2 \
\hline 75 - 79 & 77 & / / / & 3 \
\hline 80 - 84 & 82 & / / / & 3 \
\hline 85 - 89 & 87 & / / / & 3 \
\hline 90 - 94 & 92 & / / / / / & 5 \
\hline 95 - 99 & 97 & / / / & 3 \
\hline
\end{array}$$
A)1,975
B)79
C)180
D)72

Quizplus · Accepted Answer

To find the grouped mean, multiply each midpoint by its corresponding class frequency, sum these products, and then divide by the total number of scores. Calculation: $(47*1)+(52*1)+(57*2)+(62*1)+(67*1)+(72*2)+(77*3)+(82*3)+(87*3)+(92*5)+(97*3) = 1975$, and the total number of scores is $25$. Therefore, the grouped mean is $1975 / 25 = 79$.

Using the Given Frequency Distribution Table, Find the Grouped Mean