There were 12 lights in a row in a room. Initially they were all switched OFF. Anil decided to play a game. He switched ON all the lights. In the next turn he switched OFF every second light. Then, he switched ON every third light (if it was switched OFF) and so on. He continued to play similarly f…

Question

There were 12 lights in a row in a room. Initially they were all switched OFF. Anil decided to play a game. He switched ON all the lights. In the next turn he switched OFF every second light. Then, he switched ON every third light (if it was switched OFF) and so on. He continued to play similarly for 12 turns.

How many lights were switched ON after the 9th turn?

gulzar AHMAD · Answer

7

Rajput Jyoti · Answer

Please share your questions and answers

Niladri Bose · Answer

7 considering if the light she needs to turn on is already on and she leaves it that way.

Tanmoy Basak · Answer

7

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