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

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

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 ${\displaystyle \left(f_i\right)}$	Cumulative frequency (cf)
0-20	4	4
20-40	6	10
40-60	25	35
60-80	10	45
80-100	5	50
Total	${\displaystyle N=\Sigma f_i=50}$

Now, 𝑁=50 ⟹${\displaystyle \frac{N}{2}=25.}$
The cumulative frequency just greater than 25 is 35, and the corresponding class is 40-60.
Thus, the median class is 40-60.