Question

Question 6
The class marks of a frequency distribution are given as follows 15, 20, 25….. the class corresponding to the classmark 20 is:

A) 12.5 - 17.5
B) 17.5 - 22.5
C) 18.5 - 21.5
D) 19.5 - 20.5

Answer 1

The answer is B.
The difference between mid value is 5.
So, the corresponding class to the class mark 20 must have difference 5.
Therefore, option (c) and (d) are wrong.
Since, the mid value is 20 which can get only if we take option (b).
$\because \frac{17.5+22.5}{2}=\frac{40}{2}=20$