Sagot :
[tex]Multiply\ fraction\ times \ all\ distance\\\\ \frac{1}{4}*13miles=\frac{13}{4}miles=3\frac{1}{4}miles\\\\
They\ walked\ 3\frac{1}{4}miles.[/tex]
You can model the situation by 13/x=1/4, where x is the distance to otter ridge. you then cross multiply, getting you to x=52