These puzzles are deliberately NOT categorized. To do so would give a clue as to the type of answer required!
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The Divlovian Postal System
The Divlovian postal system is notoriously corrupt, and any letter, package or box that can be easily opened will be opened at the sorting office, and anything inside removed, regardless of its value. However, the corrupt sorting office staff will never bother to open anything that is locked.
Boris lives in Alphaburg, and his fiancé Natasha lives in Betaburg. Boris has bought a beautiful diamond for his bride to be and wants to get it to her as quickly as possible. Unfortunately, neither he nor her are able to travel to the other's city. He has a strongbox with a hasp that multiple padlocks can be attached to. But if he locks the diamond in the box, Natasha will be unable to open it at the other end, and he cannot send the key separately, as the envelope will be opened, and the key removed.
How can he get the gem to Natasha?
In a small village in Italy, everyone is very devout, and attends church every Sunday. What is unusual about this village is the attitude of the men to being a "cuckold" (the husband of an adulterous wife). If a husband finds out that his wife is adulterous he shoots himself in the head at dawn the next morning.
The men of the village are very proud, and honorable, and murder never takes place.
The village is very small, and word spreads very quickly. At any given moment, everyone knows whose wife has been adulterous except for the cuckolded husband. Only one man knows all the information, and that's the priest, because everyone goes to confession.
On Sunday, the priest announces that adultery has taken place in the village. Gunshots are heard on Wednesday morning at dawn. How many, and why?
The Two Trains
Two trains on the same track travel towards each other at 50 km/h. A fly begins on the front of one of the trains, and when the trains are 100km apart, it sets off at 75km/h towards the other train. When it gets there, it immediately turns back and returns to the first train. It continues in this pattern until the two trains collide. How far does it travel in this time?
The Strange Execution
Four men are sentenced to be executed, however their benevolent leader offers them a way out, if they are sufficiently clever. He arranges for them to be buried up to their necks in the sand in the desert, as shown in the diagram, in a straight line, with three on one side of a brick wall, and one on the other, each wearing either a black or white hat.
The wall cannot be seen through (i.e. A and B can only see their respective sides of the wall). They cannot turn their heads to see the people behind them. The men are blindfolded when they are buried, and know that there are two white hats and two black hats, but they do not know who is wearing which colour. C can see B, and D can see C and D. No communication is permitted between them.
In order to escape execution, one of them must call out and correctly identify the colour of their hat within ten minutes.
After 1 minute, one of them calls out. Which one, and why is he so confident about the colour of his hat?
The two jars - part one
Given a five litre jar and a three litre jar and as much water as you need, how can you measure out four litres?
The two jars - part two
A lemonade seller has two 10 gallon cans full of lemonade, but no measuring devices. Two customers arrive, each wanting two gallons of lemonade (don't ask - maybe they're just thirsty), but one has a five gallon measure and the other a four gallon measure. How can the lemonade seller do this with the minimum number of pourings?
The Insurance Salesman
An insurance salesman calls at a house, and a woman answers. She wants to get rid of him, and so says that she will buy his insurance if he can guess the age of her children.
"How many children do you have?" he asks.
"Three" she replies, "and the product of their ages is thirty six".
"I need another clue", says the insurance salesman.
"The sum of their ages is the number on the house next door."
The insurance salesman hops over the hedge to look at the house next door, but still can't work out the answer. "I need another clue", he says.
"The eldest plays the piano", says the woman.
The insurance salesman correctly guesses the ages of her children, and the woman buys the insurance.
What were the ages of her children?
Can you work out what the next letter in this sequence is?
Water Gas and Electricity
Provide supplies of Water, Gas and Electricity from each of their plants shown in the figure, to each of the houses A, B and C. No connections must cross each other.
A Handy Puzzle
If you turn a left handed glove inside out, is what you're left with right handed or left handed?
The Travelling Monk
For best entertainment give this one to a group of people, and tell them to reach consensus.
A monk decides to travel up a steep mountain to a monastery. He sets off at dawn, but his trip up the mountain is arduous, and he stops frequently to rest and to each food he has taken with him. It takes him the entire day to climb the mountain. Once there, he stays there for a week.
At the end of the week, he rises at dawn, and sets off back down the mountain. He takes the same route as before, but this time does not stop, and gets quickly back down the mountain.
Is there a point on the mountain that the monk reaches at the same time on the two days of travelling?
If a helium filled balloon is tied to the arm rest of the rear seat in my car, so that it floats in the air without touching the roof or any seats, and all the windows are shut tight, if I take a sharp left turn, what happens to the balloon? Does it swing left, swing right, stay upright, or something else? And why?
A man has a clock that keeps excellent time, but that he has unfortunately forgotten to wind. Faced with this stopped clock, he recalls his friend in town has one that's the same make. He went to visit his friend, spent the evening with him, and then returned and set his own clock. How did he do this correctly without knowing the length of the trip?
A boat is in the dock in Portsmouth Harbour, and over its side hangs a ladder. A keen observer notes that at ten o'clock the bottom four rungs are submerged. Each rung is four centimetres wide, and the rungs are 30 centimetres apart. The tide was rising at a rate of 42 centimetres per hour. How many rungs will be submerged by midday?
A man rushing to work turns on the radio. He realises then that he will be going to prison. Why?
The man from "the radio" puzzle is tried, found guilty and sentenced to death, but is given some choice in what will happen to him. He is placed in front of three doors, and given the choice of which room to go into. The first is filled with burning wood, the second is full of poisonous snakes and the third full of lions that haven't eaten for six months. Which room offers him the best chance of survival?
A cowboy rides into town on Friday, stays three nights, and then leaves on Friday. How is this possible?
There are six cakes on a plate. Six men enter the room and each take one cake. However, after they've each taken one, there is still one on the plate. How come?
|Jon Thrower © 2008|