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1000 Lockers

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1000 Lockers, 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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