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

James Bond is caught up in a mysterious scenario where the evil villain has him blindfolded. He somehow breaks through the handcuffs but is unable to get the blindfold off. Upon searching, he comes across a bow and 3 arrows. He can hear the villain speak, and thus tries to take a shot at him. He launches the first arrow, it misses the villain. He then launches the second arrow and it misses by a greater margin.

What is the probability that this third shot our James bond takes will be worse than the second shot?

Asked by Neha on 21 Jun 2023


For an extra income, John decided to work at a Hotel for one hour daily. The manager offers him that they will pay him $11 after every 11 days.
However, John offered a different proposition to the manager. The offers stand as:
He will be paid just a penny on his first day.
Two pence will be paid on the second day,
Four pence will be paid on the third day.
And so on till the 11th day.

Should the Hotel manager accept his offer?

Asked by Neha on 30 Nov 2025

What can you hold in your right hand, but never in your left hand?

Asked by Neha on 13 Jul 2025


How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

Asked by Neha on 24 Apr 2021

Can you solve the below geography rebus by decoding the below rebus ?

States Puzzle

Asked by Neha on 08 Dec 2025

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?

Asked by Neha on 17 Jan 2025


What does below science rebus mean?

Ag Ag Ag
Ag SPOON Ag
Ag Ag Ag

Asked by Neha on 11 Oct 2023

An octopus has 8 legs. A hippogriff has 6 legs and 2 pairs of wings. A sphinx has 6 legs and one pair of wings. Now we have all 3 kinds and a total of 18 insects in a cage. We have a total of 118 legs and 20 pairs of wings. How many insects do we have of each kind?

Asked by Neha on 13 Oct 2024

Find the next number in the series.
1 10 24 43 67 ?

Asked by Neha on 26 Jun 2024


In an Art Gallary, When the clock hit 11 am, Artist hung the painting number 30. When it struck 4 pm, he hung painting number 240 and when it struck 7:30 pm, he hung painting number 315.

Can you determine, which painting number will he hang when the time is 9:20 pm?

Asked by Neha on 18 Sep 2025

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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.