Question: A river is to be used for a boat race. If each boat is 3 feet across and they must have at least 2 feet between them or the riverbank, how many boats can race in a river that is 42 feet across? Think carefully first, then make a decision:
Each boat will require 3 feet across to fit itself and 2 feet space on one side for a total of 2 + 3 = 5 feet per boat. The last boat will need an additional 2 feet space on its other side, so this 2 feet should be subtracted first from the 42 feet which leaves 42 - 2 = 40 feet. 5 feet per boat on the remaining 40 feet for a total of 40 / 5 = 8 boats. So the answer is 8.