jmc

By the definition of inverse proportion, the product $jk$ is always equal to some constant $C$. Substituting the given values, we can see that $42\cdot 56=2352=C$. Using this $C$ value, we can solve for $j$ when $k=32$: $$\begin{array}{rl}j\cdot 32& =2352\\ \Rightarrow j& =\frac{2352}{32}=\boxed{73.5}\end{array}$$