Question: A machine at the soda factory can usually fill a barrel of soda in 3 minutes. However this morning a leak went unnoticed and it took 5 minutes to fill one barrel. If the leak remains undetected, how much longer will it take to fill 12 barrels of soda than on a normal day when the machine works fine? Think carefully first, then make a decision:
On a regular day it would take 3 * 12 = 36 minutes. With the leak it will take 5 * 12 = 60 minutes. It will take 60 - 36 = 24 more minutes if the leak goes undetected. So the answer is 24.