Question

Coefficient of Variation of two distribution are $60\%$ and $75\%$ and their S.D are $18$ and $15$ respectively.
Find the average of their arithmetic means.

• A. $20$
• B. $25$
• C. $30$
• D. $35$

Answer 1

Answer: (B)

$25$

Given: $C.V_1=60,C.V_2=75,S.D_1=18,S.D_2=15$
$C.V_1=\frac{S.D_1}{u_1}\times 100$
$\therefore u_1=\frac{S.D_1\times 100}{C.V_1}=30$
$C.V_2=\frac{S.D_2}{u_2}\times 100$
$\therefore u_2=\frac{S.D_2\times 100}{C.V_2}=20$
So, the average of their arithmetic means will be:
$u=\frac{u_1+u_2}{2}=25$
Ans-Option $B$.