Question

If $m\propto n$ and $m=27$ when $n=9$, find the constant of variation $\left(k\right)$.

Answer 1

Given, direct proportion is $m\propto n$
$\Rightarrow m=kn$ (where $k$ is a constant of variation)
$\Rightarrow k=\frac{m}{n}$ ....(1)
Substituting given values of $m=27$ and $n=9$ in equation (1),
$k=\frac{27}{9}=3$
$\therefore$ Constant of variation $\left(k\right)=3$.