Light the Bulbs, Riddle

There are 100 bulbs in a room. 100 strangers have been accumulated in the adjacent room. The first one goes and lights up every bulb. The second one goes and switches off all the even-numbered bulbs - second, fourth, sixth... and so on. The third one goes and reverses the current position of every third bulb (third, sixth, ninth? and so on.) i.e. if the bulb is lit, he switches it off and if the bulb is off, he switches it on. All the 100 strangers progress similarly.

After the last person has done what he wanted, which bulbs will be lit and which ones will be switched off?




Similar Riddles

I have an apple tree , number of apple in this tree get doubles every week.

On 30th week , the tree gets completely filled with apples :-)



Can you tell me , on what week does my tree is half covered with apples ?

Asked by Neha on 28 Feb 2021


John needs to purchase 100 chocolates from three different shops and he has exactly 100 rupees to do that which he must spend entirely. He must buy at least 1 Chocolate from each shop.

The first shop is selling each chocolate at 5 paise, the second is selling at 1 rupee and the third is selling at 5 rupees.

How many chocolates should he buy from each shop?

Asked by Neha on 23 Aug 2023

A newspaper is supposed to have 60 pages.Pages 14 and 21 are missing from the newspaper.

Can you tell me , Which other pages won't be there as well ?

Asked by Neha on 07 Feb 2023


There are two words one resembles the "state of rest" and the other is related to "writing/reading material".

Can you name these two words which also sound similar?

Asked by Neha on 21 May 2024

Let's play a word game. Following are some meaningless words that can be completed by adding random letters on either side of the word.

For example, the word "rdo" can be formed into "pardon".

Using the same technique, can you complete the given words?
ecalc
airb
rinci
tibac
uidel
gorit
igna
eyho

Asked by Neha on 17 Feb 2025

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

Asked by Neha on 10 Apr 2022


What does the below mathematical rebus mean?

Love the Rebus Riddle

Asked by Neha on 02 May 2026

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

Asked by Neha on 27 Oct 2021

There is a straight highway. Four different villages lie on that highway. The distance between them is different. The third village is 60km away from the first village; the fourth is 40 km away from the second; the third is 10 km near to the fourth that it is to the second.

Can you calculate the distance between the fourth and the first village ?

Asked by Neha on 23 Mar 2023


Can you count the number of lines in the below picture?

Count The Number Of Lines

Asked by Neha on 27 Dec 2023

Hot Articles

Amazing Facts

Gambling

In Canada, a mathematical puzzle must be solved in order to win the lottery to classify it as a “game of skill” not gambling.