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a selection of answers from the Dr. Math archives.
- 1000 Lockers
- The 1st student opens all 1000 lockers, the 2nd student closes
lockers 2,4,6,8,10, etc., the 3rd student opens lockers closed and
closes lockers open on lockers 3,6,9,12,15...
- Locker Problem
- There are 1,000 lockers numbered from 1 through 1,000. The first
student opens all the doors; the second student closes all the doors
with even numbers...
- Opening and Closing 1000 Lockers
- There are 1000 closed lockers and 1000 students. The first student opens
every locker; the second student reverses every other locker...
- New School Lockers
- Which locker was touched the most?
- 100 Lockers, 100 Students
- There are 100 closed lockers in a hallway, and 100 students.
Student 1 walks down the hall, opening every locker...
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