Bunuel
Hoses X and Y simultaneously fill an empty swimming pool that has a capacity of 64,000 liters. If the flow in each hose is independent of the flow in the other hose, how many hours will it take to fill the pool?
(1) Hose X alone would take 34 hours to fill the pool.
(2) Hose Y alone would take 23 hours to fill the pool.
Target question: How many hours will it take to fill the pool? Statement 1: Hose X alone would take 34 hours to fill the pool. No information about Hose Y's rate.
Statement 1 is NOT SUFFICIENT
Statement 2: Hose Y alone would take 23 hours to fill the pool. No information about Hose X's rate.
Statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined Statement 1 tells us Hose X's rate
Statement 2 tells us Hose Y's rate
Since we know the exact fill rates of each hose, we COULD determine their
combined rate, which means we COULD determine
how long will it take them to fill the pool togetherOf course, performing those tedious calculations on test day is a bad idea, since we need only determine whether or not the statements are sufficient.
Since we COULD answer the
target question with certainty, the combined statements are SUFFICIENT
Answer: