Ana and Belinda both start down a trail at the same time. Belinda rides her bike at a speed of 10 miles per hour. It takes Belinda 45 minutes to arrive at the end of the trail. How long is the trail? How long will it take Ana to complete the trail?

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