the graph shows the time and distance that a horse ran around a track if the horse runs at that same speed, how long will it take the horse to run 1.5 miles?

Using the values given at the red dot, the horse ran 0.2 miles in 20 seconds.
Divide 1.5 miles by 0.2:
1.5 / 0.2 = 7.5
Multiply that number by 20 seconds:
7.5 x 20 = 150 seconds
1 minute = 60 seconds
150 / 60 = 2.5
It will take 2.5 minutes to run 1.5 miles