Kyle spentof an hour on the level ground part of the length 4 = miles. Then he spent = of an hour on the uphill part of the same length 4 = miles. Finally, he spent of an hour on the downhill part of the same length 4 = miles. In all, he spent = = = hours for the entire 12-miles trip. ANSWER. His trip took hours = hours = 1 hour and 20 minutes.