Prisoners got freed

100 prisoners are stuck in the prison in solitary cells. The warden of the prison got bored one day and offered them a challenge. He will put one prisoner per day, selected at random (a prisoner can be selected more than once), into a special room with a light bulb and a switch which controls the bulb. No other prisoners can see or control the light bulb. The prisoner in the special room can either turn on the bulb, turn off the bulb or do nothing. On any day, the prisoners can stop this process and say "Every prisoner has been in the special room at least once". If that happens to be true, all the prisoners will be set free. If it is false, then all the prisoners will be executed. The prisoners are given some time to discuss and figure out a solution. How do they ensure they all go free?




Similar Riddles

Count the number of triangles in the picture below:

Counting You Should Know

Asked by Neha on 16 Jul 2024


81 x 9 = 801. What must you do to make the this equation true?

Asked by Neha on 03 Oct 2021

A girl says this to her best friend: “I was born in 1955, and I celebrated my 17th birthday last weekend.” Her best friend thinks she’s lying, but she’s actually correct. How is that possible?

Asked by Neha on 12 Jun 2025


The doctor advised his patient to take a tablet after every fifteen minutes. He gave him five tablets in total.

How much time will he take to have all the five tablets?

Asked by Neha on 01 Aug 2023

Bopanna was working on a murder case when he received a message about the location of the murder weapon.
The message was encrypted as below.

"deb mitciv eht edisni neddih si nopaew redrum ehT"

Tell me the location of the murder weapon.

Asked by Neha on 04 Jan 2026

How can you make number one disappear by adding something to it?

Asked by Neha on 08 May 2024


Solve below popular number sequence
314 159 265 358 979 323 846 ?

Asked by Neha on 09 Nov 2025

Tell me the Hindi name of a Vegetable which if we remove 1st word will become a precious Stone and by removing the last word it will become a sweet eatable.

Asked by Neha on 16 Apr 2025

"That Restaurant always remains crowded. This is the reason why nobody goes there".

Can you find a flaw in this statement?

Asked by Neha on 06 Apr 2024


You have 1023 apples and 10 bags. You have to distribute these apples in these 10 bags in any way you choose. But when I ask for a certain number of apples you have to give them in terms of bags without transferring the apples from other bags. How do you distribute the apples?

Asked by Neha on 25 Jan 2021

Hot Articles

Amazing Facts

Artificial Intelligence

Artificial Intelligence has crushed all human records in the puzzle game “2048,” achieving a high score of 839,732 and beating the game in only 973 moves without using any undo.