To find out how far Grace ran in 1.5 hours, we first need to determine her speed in miles per hour.
Grace ran 26 miles in 4 hours. Her speed can be calculated as follows:
Speed = Distance / Time = 26 miles / 4 hours = 6.5 miles per hour.
Now, we can find out how far she ran in 1.5 hours using the speed we just calculated:
Distance = Speed × Time = 6.5 miles/hour × 1.5 hours = 9.75 miles.
So, Grace ran 9.75 miles in 1.5 hours.