Question

In the tables given below, class-mark and frequencies is given. Construct the frequency tables taking inclusive and exclusive classes.

(i)

Class width	Frequency
5	3
15	9
25	15
35	13

(ii)

Class width	Frequency
22	6
24	7
26	13
28	4

Answer 1

In the tables given below, class-mark and frequencies is given. Construct the frequency tables taking inclusive and exclusive classes.

(i)

Class-mark	Frequency
5	3
15	9
25	15
35	13

We have, class size = $15-5=10$

Since, the lower limit of class-mark 5$=5-\frac{10}{2}=0$ and the upper limit $=5+\frac{10}{2}=10$.

So, the exclusive frequency table is given by:

Class	Frequency
0-10	3
10-20	9
20-30	15
30-40	13

Also, the inclusive frequency table is given by:

Class	Frequency
0-10	3
11-20	9
21-30	15
31-40	13

(ii)

Class-mark	Frequency
22	6
24	7
26	13
28	4

We have, class size = $24-22=2$

Since, the lower limit of class-mark 22$=22-\frac{2}{2}=21$ and the upper limit$=22+\frac{2}{2}=23$.

So, the exclusive frequency table is given by:

Class	Frequency
21-23	6
23-25	7
25-27	13
27-29	4

Also, the inclusive frequency table is given by:

Class	Frequency
20-22.5	6
23-25.5	7
25-27.5	13
27-29.5	4

Disclaimer: The exclusive frequency table can vary from student to student. The "Class width" is replaved by "Class-marks" according to the question.