THE PUZZLET PAGE
PUZZLET 054
Empty Bottles
| 1,000
bottles are empty. Every
2nd bottle is now filled with water. After this, every 3rd bottle is
examined. If it's empty, it has to be filled. If it already contained water, it has to be emptied. The whole process is repeated for every 4th bottle, then every 5th, and so on up to the 1,000th. At the end of the process, what bottles, if any, will be empty? |
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