Question

In a class test, 50 students obtained marks as follows:

Marks obtained	0−20	20−40	40−60	60−80	80−100
Number of students	4	6	25	10	5

Find the modal class and the median class. [CBSE 2014]

Answer 1

Here the maximum class frequency is 25, and the class corresponding to this frequency is

40−60.

So, the modal class is 40−60.

Now, to find the median class let us put the data in the table given below:

Marks obtained	Number of students (fi)	Cumulative frequency (cf)
0−20	4	4
20−40	6	10
40−60	25	35
60−80	10	45
80−100	5	50
Total	N = ∑fi = 50

Now,

N= 50 ⇒$\frac{N}{2}$=25.

The cumulative frequency just greater than 25 is 35, and the corresponding class is 40−60.

Thus, the median class is 40−60.

Hence, the modal class is 40−60. and the median class is also 40−60.