Lizzy: An old car can drive 8 miles in one hour. After 5 hours of constant driving, the car needs to get cooled down which takes 1 hour. How many miles can this car drive in 13 hours?.
Me: Hmmm, let me think. I think this is the detailed solution:
In 5 hours the car can drive 8 * 5 = 40 miles. One cycle of driving and pause takes 5 + 1 = 6 hours. In 13 hours this cycle can fit 13 / 6 = 2 full cycles with a remainder of 1 hour. Two cycles will last for 2 * 6 = 12 hours. During two full cycles, the car will drive 40 * 2 = 80 miles. So there is 13 - 12 = 1 remaining hour when the car can drive. That means during 13 hours the car will be able to drive 80 + 8 = 88 miles. Final answer: 88.