Chapter 9 - Section 9.4 - Variation and Problem Solving - Exercise Set - Page 662: 17

The constant of variation is $2$. The inverse variation equation is $y=\frac{2}{x}$.

$y=\frac{k}{x}$ $y=\frac{1}{8}; x=16$ $\frac{1}{8}=\frac{k}{(16)}$ $\frac{1}{8}\times16=k$ $2=k$ The constant of variation is $2$. The inverse variation equation is $y=\frac{2}{x}$.