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Once in a prison with 100 prisoners, the Warden introduces a strange but interesting challenge to all the prisoners. This challenge can even grant them the freedom and thus every one of the prisoners becomes quite excited.

The warden selects one prisoner everyday randomly from the lot and moves him into a pitch black room with a bulb and a witch that controls the bulb. The prisoner can carry out three different actions in the room - He can switch on the bulb, switch it off or do nothing and sit idle. A prisoner can be picked up more than one time.

Now the warden introduces the twist in the challenge. He tells them that the prisoners can put a stop to the process any day they feel that every one of them has been confined to that room at least once. If the prisoners are correct, then every single one of them will be set free. But if they have put up a wrong judgment, all of them will be killed.

Seeking it to be the only chance of freedom, the prisoners take up the challenge. They are given some time to discuss regarding it before the process could begin. How will they plan things so that they are finally set free?

The warden selects one prisoner everyday randomly from the lot and moves him into a pitch black room with a bulb and a witch that controls the bulb. The prisoner can carry out three different actions in the room - He can switch on the bulb, switch it off or do nothing and sit idle. A prisoner can be picked up more than one time.

Now the warden introduces the twist in the challenge. He tells them that the prisoners can put a stop to the process any day they feel that every one of them has been confined to that room at least once. If the prisoners are correct, then every single one of them will be set free. But if they have put up a wrong judgment, all of them will be killed.

Seeking it to be the only chance of freedom, the prisoners take up the challenge. They are given some time to discuss regarding it before the process could begin. How will they plan things so that they are finally set free?

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Three men are living in a desert namely – Alex, Brian and Chris.

Alex hates Chris and thus he decides to kill him. To succeed in his evil intentions, he poison the water supply of Chris. Since they are living in desert, he will have to drink water or he will die of thirst.

Brian is not aware of the actions of Alex and he plans to kill Chris as well. To do this, he killed the water supply of Chris.

Chris dies due to his thirst. Who killed him?

Alex hates Chris and thus he decides to kill him. To succeed in his evil intentions, he poison the water supply of Chris. Since they are living in desert, he will have to drink water or he will die of thirst.

Brian is not aware of the actions of Alex and he plans to kill Chris as well. To do this, he killed the water supply of Chris.

Chris dies due to his thirst. Who killed him?

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In front of you, there are 9 coins. They all look absolutely identical, but one of the coins is fake. However, you know that the fake coin is lighter than the rest, and in front of you is a balance scale. What is the least number of weightings you can use to find the counterfeit coin?
**category** :
LOGIC

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Let us say that a table tennis tournament was going on with knock out terms which means the one who loses the match is out of the tournament. 100 players took part in that tournament.

How many matches were played?

How many matches were played?

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There are 100 doors. 100 strangers have been gathered in the adjacent room. The first one goes and opens every door. The second one goes and shuts down all the even numbered doors – second, fourth, sixth... and so on. The third one goes and reverses the current position of every third door (third, sixth, ninth… and so on.) i.e. if the door is open, he shuts it and if the door is shut, he switches opens it. All the 100 strangers progresses in the similar fashion.

After the last person has done what he wanted, which doors will be left open and which ones will be shut at the end?
**category** :
LOGIC

After the last person has done what he wanted, which doors will be left open and which ones will be shut at the end?

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Rooney, Hernandez, and Robin race each other in a 100 meters race. All of them run at a constant speed throughout the race.

Rooney beats Hernandez by 20 meters.

Hernandez beats Robin by 20 meters.

How many meters does Rooney beat Robin by ?

Rooney beats Hernandez by 20 meters.

Hernandez beats Robin by 20 meters.

How many meters does Rooney beat Robin by ?

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30 classmates went for a bonfire. While sitting around the fire, they decided to play a game. To play it, they divided themselves into 5 teams in a way that there were 5 rows having 7 people each.

How can this arrangement be possible while sitting around the bonfire?

How can this arrangement be possible while sitting around the bonfire?

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This one is a bit of tricky river crossing puzzle than you might have solved till now. We have a whole family out on a picnic on one side of the river. The family includes Mother and Father, two sons, two daughters, a maid and a dog. The bridge broke down and all they have is a boat that can take them towards the other side of the river. But there is a condition with the boat. It can hold just two persons at one time (count the dog as one person).

No it does not limit to that and there are other complications. The dog can’t be left without the maid or it will bite the family members. The father can’t be left with daughters without the mother and in the same manner, the mother can’t be left alone with the sons without the father. Also an adult is needed to drive the boat and it can’t drive by itself.

How will all of them reach the other side of the river?

No it does not limit to that and there are other complications. The dog can’t be left without the maid or it will bite the family members. The father can’t be left with daughters without the mother and in the same manner, the mother can’t be left alone with the sons without the father. Also an adult is needed to drive the boat and it can’t drive by itself.

How will all of them reach the other side of the river?

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You need to divide 50 marbles(25-red and 25-blue) into two boxes such that the probability of picking red marble is maximized.

Following conditions need to hold true :

1. None of box is empty

2. All the marbles must be in one of two boxes.
**category** :
LOGIC

Following conditions need to hold true :

1. None of box is empty

2. All the marbles must be in one of two boxes.

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There are three bags.The first bag has two blue rocks. The second bag has two red rocks. The third bag has a blue and a red rock. All bags are labeled but all labels are wrong.You are allowed to open one bag, pick one rock at random, see its color and put it back into the bag, without seeing the color of the other rock.

How many such operations are necessary to correctly label the bags ?

How many such operations are necessary to correctly label the bags ?

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