Question

Given below is a cumulative frequency distribution showing the marks secured by 50 students of a class:

Marks	Below 20	Below 40	Below 60	Below 80	Below 100
Number of students	17	22	29	37	50

Form the frequency distribution table for the data.

Answer 1

Here, we observe that, 17 students have scored marks below 20 i.e., it lies between class interval 0 – 20 and 22 students have scored marks below 40, so 22 – 17 = 5 students lies in the class interval 20 – 40 continuing in the same manner, we get the complete frequency distribution table for given data.

Marks	Number of students
0 – 20	17
20 – 40	22 – 17 = 5
40 – 60	29 – 22 = 7
60 – 80	37 – 29 = 8
80 – 100	50 – 37 = 13