Question

Q1) Calculate Harmonic Mean for the following
C.I. 20-29 30-39 40-49 50-59 60-69 F 3 5 20
10 5​

Answer 1

Answer:

Explanation:

Here the maximum class frequency is 50 and the class corresponding to this frequency is 40-49.

So, the modal class is 40-49.

The lower limit of modal class 40-49 is l = 40.

Class size c = 10

Frequency of the modal class f1​=50.

Frequency of the class preceding the modal class f0​=20.

Frequency of the class succeeding the modal class f2​=30.

z=l+(2f1​−f0​−f2​f1​−f0​​)×c

=40+(2×50−20−3050−20​)×10

=40+5030​×10

=40+6

=46

The mode for the given data is 46