Question

the class marks in frequency distribution are 19.5, 26.5, 33.5, 40.5, then find the

class corresponding to the class mark 33.5.​

Answer 1

Step-by-step explanation:

Class mark is the mid point of the class interval.

Class size is the upper limit minus lower limit.

Given that class mark of a class is 6.5 and

the class size is 26.5−19.5=33.5−26.5=40.5−33.5=7

By option verification,

Opition A class mark is

16+23 ÷ 2 = 39÷2

=19.5

False

Option B class mark is

30+23 ÷2

= 53 ÷ 2

=26.5

False

Option C class mark is

30+37 ÷ 2

= 67 ÷ 2

=33.5

and class size is 37−30=7

True

Option D class mark is

37+41÷2

=78÷2

=39

False

Therefore the class interval is 30−37