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The 100 Lockers Riddle
which lockers end up open?
A school has 100 closed lockers and 100 students. Student 1 opens every locker. Student 2 toggles every 2nd locker, closing it if open and opening it if closed. Student 3 toggles every 3rd locker, and so on up to student 100. Which lockers are open at the end?
Source: A classic puzzle, retold by INFINITE SUM and fact-checked against our curated notes
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