Consider the relative frequency distribution given below:
$$\begin{array} { l c }
\text { Class Interval } & \text { Relative Frequency } \
\text { 20-under } 40 & 0.2 \
40 \text {-under } 60 & 0.3 \
60 \text {-under } 80 & 0.4 \
\text { 80-under } 100 & 0.1
\end{array}$$
There were 60 numbers in the data set.How many of the number were less than 80?
A)90
B)80
C)0.9
D)54
E)100

Question

Consider the relative frequency distribution given below: 
$$\begin{array} { l c } 
\text { Class Interval } & \text { Relative Frequency } \
\text { 20-under } 40 & 0.2 \
40 \text {-under } 60 & 0.3 \
60 \text {-under } 80 & 0.4 \
\text { 80-under } 100 & 0.1
\end{array}$$
There were 60 numbers in the data set.How many of the number were less than 80?
A)90
B)80
C)0.9
D)54
E)100

Quizplus · Accepted Answer

The relative frequencies for intervals less than 80 sum up to 0.2 + 0.3 + 0.4 = 0.9. Since there are 60 numbers in the data set, the number of numbers less than 80 is 0.9 * 60 = 54.

Consider the Relative Frequency Distribution Given Below There Were 60 Numbers in the Data Set