Question

Find the modal and median classes of the following distribution.

Class	0 – 20	20 – 40	40 – 60	60 – 80	80 – 100
Frequency	11	22	19	18	7

Answer 1

Class	Frequency	cf
0 – 20	11	11
20 – 40	22	33
40 – 60	19	52
60 – 80	13	65
80 – 100	7	72
	`sumf_i` = 72

Here, highest frequency is 22

Hence, modal class is 20 – 40

Also, N = `sumf_i` = 72

Now, `N/2 = 72/2` = 36

36 lies in cumulative frequency 52

So, median class is 40 – 60.