If in one hour Belinda can go 10 miles that means in 30 minutes she can go 5 miles. 60/2=30 10/2=5
If she can go 5 miles is 30 minutes than by doing some simple math she must be able to go 2.5 miles in 15 mins. 30/2=15 5/2=2.5
Meaning that when you add 30+15 you get 45 and when you add the distance she can go in each amount of given time 5+2.5 you get 7.5
- So the trail has to be 7.5 miles long
