Two water pumps are filling a pool. One of the pumps is high power and can fill the pool 5 hours before the other can do. However, they both working together can fill half of the pool in 3 hours. In how many hours the high power pump can fill the pool?
With 8 pumps it takes 32 hours to fill a pool. We know this is inverse variation so all the products are the same. 32 * 8 = 256, so now we know we can get the answer by diving 256 by 4, getting 64.
