Coefficient of variation of two distributions are 60% and 70% and their standard deviations are 21 and 16 respectively. What are their arithmetic means?

Explanation

Coefficient of variation `=\frac{\sigma}{\bar{x}} \times 100`
So, we have:
$$ \begin{aligned} &60 \%=\frac{21}{\bar{x}} \times 100 \Rightarrow \bar{x}=\frac{21}{.60} \times 100=35 \\ &70 \%=\frac{16}{\bar{x}} \times 100 \Rightarrow \bar{x}=\frac{16}{.70} \times 100=22.85 \end{aligned} $$