Question: A marathon is 26 miles. He can run the first 10 miles in 1 hour. For the remaining miles he runs at 80% that pace. How long does the race take? Think carefully first, then make a decision:
There are 26 - 10 = 16 miles left for the rest of the race. He runs 10 * .8 = 8 miles per hour. So it takes him 16 / 8 = 2 hours. So in total it takes 1 + 2 = 3 hours. So the answer is 3.