Answer
The ratio of the width to the perimeter of the swimming pool is $\frac{1}{5}$
Work Step by Step
The ratio of x to y is equal to $\frac{x}{y}$. $\frac{5}{1}$ is the incorrect ratio because the value of the width is $30$ feet and the value of the perimeter is $150$ feet. $\frac{30}{150} = \frac{1}{5}$ and not $\frac{5}{1}$.