Question

The median class for the following data is
$\begin{array}{cccccc}\text{Marks}& \text{Below 10}& \text{Below 20}& \text{Below 30}& \text{Below 40}& \text{Below 50}\\ \text{No. of students}& & & & & \\ \text{(Cumulative frequency}& \text{5}& \text{10}& \text{23}& \text{31}& \text{40}\end{array}$

• A. 10-20
• B. 20-30
• C. 30-40
• D. 40-50

Answer 1

The correct option is B

20-30

The given table can be written as:
$\begin{array}{cccccc}\text{Marks}& \text{0-10}& \text{10-20}& \text{20-30}& \text{30-40}& \text{40-50}\\ \text{No. of students}& & & & & \\ \text{(Cumulative frequency)}& \text{5}& \text{10}& \text{23}& \text{31}& \text{40}\end{array}$

Since there are a total of 40 observations, the median class is the one whose cumulative frequency is closest to and greater than 20. The class interval 20-30 is the required answer.