Step-by-step explanation: Daisy ran 12 miles in 90 minutes so we should first figure out how many minutes it took her to run a mile. So 90/12 would get us that. 90/12 turns out to be 7.5 minutes per mile. Since she runs at a constant rate we multiply 7.5 by 3 (7.5*3) to get 22.5 minutes for 3 miles.
