Question

The class mark of a frequency distribution are 15, 20, 25, 30......, write class corresponding to the class mark. ​

Answer 1

Class size ,h =class mark2 -class marks1

Therefore, class size =20-15=5

Lower class limit of class corresponding to class mark 15= class mark- (h÷2)

= 15 - 5/2

= 12.5

Similarly,

Upper Class limit of the same class=15+ h/2

= 17.5

Thus, Corresponding Classes to class marks 15, 20, 25, 30,... respectively=12.5-17.5, 17.5-22.5, 22.5-27.5, 27.5-32.5,....

Answer 2

Answer:

i. Calculate the frequency of class 30 -40.

ii. Calculate the class mark of class 10 - 25