Hi there!
In order to figure this out, we'll need to set up a proportion. This is the proportion we'll use: 10/85 = 8/x. Then, we need to cross-multiply: 10x = 680. Lastly, we'll divide both sides by 10 to figure out how long it takes to run 8 miles: x = 68 minutes.
Hope this helps!! :)
If there's anything else that I can help you with, please let me know!