Write the class-size in each of the following:
(i) 0 – 4, 5 – 9, 10 – 14
(ii) 10 – 19, 20 – 29, 30 – 39
(iii) 100 – 120, 120 – 140, 160 – 180
(iv) 0 – 0.25, 0.25 – 0.50, 0.50 – 0.75
(v) 5 – 5.01, 5.01 − 5.02, 5.02 – 5.03
Solution
(i) 0 - 4, 5 - 9,10 - 14.
True class limits are 0.5- 4.5,4.5 - 9.5,9.5 - 14.5.
∴Class size=14.5-9.5 = 5
(ii) 10 - 19, 20 - 29, 30 - 39.
True class limits →10.5-19.5,19.5 - 29.5,29.5-39.5
Class size = 39.5-29.5
=10
(iii) 100 - 120,120 - 140,160 - 180.
Here the class limits and true class limits are the same
∴Class size 120-100=20
(iv) 0 - 0.25, 0.25-0.50, 0.50 - 0.75
Here the class limits and true class limits are the same
∴Class size = 0.25 - 0 = 0.25
(v) 5-5.01, 5.01-5.02, 5.02 - 5.03.
Here the class limits ad true class limits are the same
∴Class size = 5.01-5.0 = 0.01.