The test scores of 40 students are summarized in the frequency distribution below. Find the standard deviation.
$\begin{array}{r|c}
\text { Score } & \text { Students } \
\hline 50 \text {-under } 60 & 8 \
60 \text {-under } 70 & 15 \
70 \text {-under } 80 & 6 \
80 \text {-under } 90 & 5 \
90 \text {-under } 100 & 6
\end{array}$
A)$13.5$
B) $12.2$
C) $14.2$
D) $12.8$

Question

The test scores of 40 students are summarized in the frequency distribution below. Find the standard deviation. 
$\begin{array}{r|c}
\text { Score } & \text { Students } \
\hline 50 \text {-under } 60 & 8 \
60 \text {-under } 70 & 15 \
70 \text {-under } 80 & 6 \
80 \text {-under } 90 & 5 \
90 \text {-under } 100 & 6
\end{array}$  
A)$13.5$
B) $12.2$
C) $14.2$
D) $12.8$

Quizplus · Accepted Answer

The Answer of The test scores of 40 students are summarized in the frequency distribution below. Find the standard deviation. 
$\begin{array}{r|c}
\text { Score } & \text { Students } \
\hline 50 \text {-under } 60 & 8 \
60 \text {-under } 70 & 15 \
70 \text {-under } 80 & 6 \
80 \text {-under } 90 & 5 \
90 \text {-under } 100 & 6
\end{array}$  
A)$13.5$
B) $12.2$
C) $14.2$
D) $12.8$

The Test Scores of 40 Students Are Summarized in the Frequency