Monday, October 29, 2012

Puzzle 20: Survivors Issue

Puzzle 20: A group of Englishmen are travelling on a German plane, piloted by an Norwegian, bound for Finland. If the plane was to crash in Sweden, where would the survivors be buried?
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Puzzle 19: 1 sheep for 3 animals

Puzzle 19: A lion can consume one sheep in two hours, a wolf can consume three sheep in eight hours and a hyena can consume one sheep in eight hours. If all of the animals were in a cage and were given a sheep, how long would it take them to consume it?

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Puzzle 18: Misfortune Clock

Puzzle 18: You have the misfortune to own an unreliable clock. This one loses exactly 20 minutes every hour. It is now showing 4:00am and you know that is was correct at midnight, when you set it. The clock stopped 4 hours ago, what is the correct time now?

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Friday, October 26, 2012

Puzzle 17: Top 3 among 25 horses

Puzzle 17: You have 25 horses. When they race, each horse runs at a different, constant pace. A horse will always run at the same pace no matter how many times it races.
You want to figure out which are your 3 fastest horses. You are allowed to race at most 5 horses against each other at a time. You don't have a stopwatch so all you can learn from each race is which order the horses finish in.
What is the least number of races you can conduct to figure out which 3 horses are fastest?

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Puzzle 16: 10 Cigarette Butts

Puzzle 16: Bruce is an inmate at a large prison, and like most of the other prisoners, he smokes cigarettes. During his time in the prison, Bruce finds that if he has 3 cigarette butts, he can cram them together and turn them into 1 full cigarette. Whenever he smokes a cigarette, it turns into a cigarette butt.
One day, Bruce is in his cell talking to one of his cellmates, Steve.
"I really want to smoke 5 cigarettes today, but all I have are these 10 cigarette butts," Bruce tells Steve. "I'm not sure that will be enough."
"Why don't you borrow some of Tom's cigarette butts?" asks Steve, pointing over to a small pile of cigarette butts on the bed of their third cellmate, Tom, who is out for the day on a community service project.
"I can't," Bruce says. "Tom always counts exactly how many cigarette butts are in his pile, and he'd probably kill me if he noticed that I had taken any."
However, after thinking for a while, Bruce figures out a way that he can smoke 5 cigarettes without angering Tom. What is his plan?

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Thursday, October 25, 2012

Puzzle 15: Racing position.

Puzzle 15: In the final stretch of a road race, you pass the 2nd-place runner right before crossing the finish line. What place do you finish in?
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Puzzle 14: Sitting in a plane

Puzzle 14: People are waiting in line to board a 100-seat airplane. Steve is the first person in the line. He gets on the plane but suddenly can't remember what his seat number is, so he picks a seat at random. After that, each person who gets on the plane sits in their assigned seat if it's available, otherwise they will choose an open seat at random to sit in.
The flight is full and you are last in line. What is the probability that you get to sit in your assigned seat? 

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Puzzle 6: Probability problem

Puzzle 6: Suppose there are 3 ants at the edge of each triangle. Suppose each ant can move either in clockwise or anti-clockwise direction only. What is the probability that they will not collide?
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Puzzle 5: Hat and man problem

Puzzle 5: Solve the following puzzle:
There are 2 Red and 2 Black hats. Every person is wearing one hat, anyone can tell the color of his hat and all 4 will be free. There is only one chance to say the color by anyone.
Conditions are:
a) Person 1 & person 2 can see only wall.
b) Person 3 can see person 1 and wall.
c) Person 4 can see person 1&2 and wall. 

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Puzzle 4: Shoot the crazy monkey

Puzzle 4: There 5 trees in a row. There is one monkey on the tree who is physic. You have to shot him with your gun. But he is very smart too. You are allowed to shoot on any tree, if monkey is on that tree then he will die, else he will make jump to next or previous tree for sure. You can only see monkey if he die.

How many shots(maximum shots) you need to make sure that monkey get killed.
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Puzzle 3: Bees & Flowers Problem

Puzzle 3: In a place some bees and flowers are there..If every flower shares by a 1 bee then 1 bee will remain. If every flower shares by 2 bees then flower will remain. Then how many flowers & bees?

How many shots(maximum shots) you need to make sure that monkey get killed.
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Puzzle 2: Score century in 3 balls

Puzzle 2: If two batsmen in the match both r at 94 and last 3 balls remaining 7 to win both two batsmen got 100. How?
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Advanced Problem: Now if players are not out.
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Puzzle 1: Cross river problem

Puzzle 1: 3 Devils and 3 men, cross the river. More Devils will eat man. How to cross, anyone can drive the boat.
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Puzzle 10: Truth and Liar among 3 friends

Puzzle 10: There are 3 friends say A, B, C. Of them, C knows one of A/B speaks always the truth and the other speaks always lies. One day, all of them meet with a car accident. Unfortunately, both A and B die on the spot, and C joins them a bit late. When C reaches the alien world, he wants to goto heaven. He only sees 2 exits. So, he assumes one exit for heaven and the other exit for hell. He also recognizes both A and B as security guards standing at each of the exits. Now, knowing one of A/B speaks truth and the other lies always, C needs to find way to heaven, by asking only ONE question to each of the security at the exits? How?
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Puzzle 9: Wrong labels on vending machine

Puzzle 9: There is vending machine. Orange, Apple, Oracle/Apple. And all of them have wrong label. How to find the correct machine in one attempt?
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Puzzle 8: One defected apple in 10 boxes

Puzzle 8: There are 10 boxes of apples. Each apple in the boxes weights 1 pound, except that one of the boxes contains bad apples, which weights 0.9 pound each. You are given a digital weight (not a scale), and you can take apples out of the boxes. What is the minimum time of weighs to find out which box has bad apples?

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Puzzle 7: Figure out the liar

Puzzle 7: There is a T point and you are coming from one other side. You have to go towards TrueValley as there is no sign board for the same at T-point. There is one person standing at T-point whom you are allowed to ask only question. But the answer depends on following case:
a)      Person from TrueValley always say truth.
b)      Person from FalseValley always say false.
c)       You don’t know the person standing is from which valley.
What will be your question to find your way?
Solution: Invite him and say you will drop him at his home. There can be two cases only.
a)      Person is from TrueValley then he will take towards his home i.e. TrueValley which is your destination.
b)      Person is from FalseValley then he will take towards other route instead of his home which was FalseValley. As he is a lier so will never ever take you towards his home.

Puzzle 11: 12 balls, one is defective

Puzzle 11: Suppose you have 12 balls. One of them is defective(whether light or heavy). You need to find out the defective one by using the weight scale 3 times only.
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Puzzle 13: 100 Prisoner + One Light Bulb

Puzzle 13: There is a prison with 100 prisoners, each in separate cells, which are sealed off, soundproof and windowless. There is a lobby in the prison with a lightbulb in it. Each day, the warden will pick one of the prisoners at random (even if they have been picked before) and take them out to the lobby. The prisoner will have the choice to flip the lightbulb switch if they want. The lightbulb starts in the "off" position.

When a prisoner is brought out to the lobby, he also has the option of saying "Every other prisoner has been brought out to the lobby." If a prisoner chooses to say this and it is true, all the prisoners will go free. However, if a prisoner chooses to say this and it's wrong, all the prisoners will be executed. So a prisoner should only say this if he knows it is true for sure.

Before the first day of this process begins, all the prisoners are allowed to get together to discuss a strategy to eventually save themselves.

What strategy could they use to ensure their eventual salvation?
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Puzzle 12: Two paper cubes

Puzzle 12: A man has two paper cubes on his desk. Every day he arranges both cubes so that the front faces show the current day of the month. What numbers are required on the faces of the cubes to allow this for all possible days in the calendar?
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