3 Little Monkeys
There are three monkeys sitting in a tree after a meal. Then they fall asleep. One falls asleep for 66 minutes at a time. Another falls asleep for 81 minutes at a time. The last monkey falls asleep for 33 minutes at a time. Suppose that when they wake up they just open their eyes, then fall asleep again. In how many minutes will all three monkeys be awake?