#### Answer

The required value is $k=8$

#### Work Step by Step

The provided equation is, $S=\frac{kA}{P}$
Put the values of A, P and S in the formulae.
$\begin{align}
& 12000=\frac{k\times 60000}{40} \\
& k=\frac{12000\times 40}{60000} \\
& k=8
\end{align}$
Therefore, the value of $k=8$.