The following frequency distribution analyzes the scores on a math test. Find the class boundaries of scores interval 90-99. $$\begin{array} { | l c | }
\hline \text { Scores } & \text { Number of students } \
50 - 59 & 2 \
60 - 69 & 4 \
70 - 79 & 6 \
80 - 89 & 15 \
90 - 99 & 5 \
\hline
\end{array}$$
A) 89.5, 100.5
B) 89.5, 100.4
C) 89.5, 99.5
D) 90.5, 99.5

Question

The following frequency distribution analyzes the scores on a math test. Find the class boundaries of scores interval 90-99. $$\begin{array} { | l c | } 
\hline \text { Scores } & \text { Number of students } \
50 - 59 & 2 \
60 - 69 & 4 \
70 - 79 & 6 \
80 - 89 & 15 \
90 - 99 & 5 \
\hline
\end{array}$$
A) 89.5, 100.5
B) 89.5, 100.4
C) 89.5, 99.5
D) 90.5, 99.5

Quizplus · Accepted Answer

The class boundaries are the lower and upper limits of each class interval. The lower boundary of a class interval is the midpoint of the previous interval, and the upper boundary is the midpoint of the next interval. For the class interval 90-99, the lower boundary is (80+90)/2 = 89.5 and the upper boundary is (99+100)/2 = 99.5.

The Following Frequency Distribution Analyzes the Scores on a Math