Riddle #806

logic

Suitcase Locks

A man needs to send important documents to his friend across the country. He buys a suitcase to put the documents in, but he has a problem: the mail system in his country is very corrupt, and he knows that if he doesn't lock the suitcase, it will be opened by the post office and his documents will be stolen before they reach his friend. There are lock stores across the country that sell locks with keys. The only problem is that if he locks the suitcase, he has no way to send the key to his friend so that the friend will be able to open the lock: if he doesn't send the key, then the friend can't open the lock, and if he puts the key in the suitcase, then the friend won't be able to get to the key. The suitcase is designed so that any number of locks can be put on it, but the man figures that putting more than one lock on the suitcase will only compound the problem. After a few days, however, he figures out how to safely send the documents. He calls his friend who he's sending the documents to and explains the plan. What is the man's plan?
The plan is this: 1. The man will put a lock on the suitcase, keep the key, and send the suitcase to his friend. 2. The friend will then put his own lock on the suitcase as well, keep the key to that lock, and send the suitcase back to the man. 3. The man will use his key to remove his lock from the suitcase, and send it back to the friend. 4. The friend will remove his own lock from the suitcase and get to the documents.
93.39 %
38 votes

Similar riddles

See also best riddles or new riddles.

logicmath

Equation riddle

If, Fernando + Alonso + McLaren = 6 Fernando x Alonso = 2 Alonso x McLaren = 6 Then, McLaren x Fernando =?
3 Explanation: Fernando + Alonso + McLaren = 6 Fernando x Alonso = 2 Alonso x McLaren = 6 Given. Fernando x Alonso = 2 Alonso x McLaren = 6 Rewriting Both equations in terms of Alonso, Fernando = 2/Alonso McLaren = 6/Alonso Replacing above values in equation "Fernando + Alonso + McLaren = 6" 2/Alonso + Alonso + 6/Alonso =6 (2 + Alonso^2 + 6)/Alonso = 6 8 + Alonso^2 = 6Alonso Alonso^2 - 6Alonso + 8 = 0 (Alonso - 4) (Alonso - 2) = 0 Therefore; Alonso = 4 or 2 Let's take value of Alonso as 2 Fernando = 2/2 = 1 McLaren = 6/2 = 3 Therefore; McLaren x Fernando = 3 x 1 = 3
90.47 %
44 votes

funnylogicshort

Digging a hole

If it takes one man three days to dig a hole, how long does it take two men to dig half a hole?
You can’t dig half a hole.
92.86 %
35 votes

cleanfunnylogiclove

Love triangle

A doctor and a bus driver are both in love with the same woman, an attractive girl named Sarah. The bus driver had to go on a long bustrip that would last a week. Before he left, he gave Sarah seven apples. Why?
An apple a day keeps the doctor away!
83.71 %
83 votes

cleanlogicmysteryshort

The casino rooster

A man owned a casino and invited some friends. It was a dark stormy night, and they all placed their money on the table right before the lights went out. When the lights came back on, the money was gone. The owner put a rooster in an old rusty tea kettle. He told everyone to get in line and touch the kettle after he turned the lights off, and the rooster will crow when the robber touched it. After everyone touched it, the rooster didn't crow, so the man told everyone to hold out their hands. After examining all the hands, he pointed out who the robber was. How did he know who stole the money?
Because the tea kettle was rusty, whoever touched it would have rust on their hands. The robber didn't touch the kettle, therefore he was the only one whose hands weren't rusty.
80.62 %
56 votes

logic

An iron horse with a flaxen tail

An iron horse with a flaxen tail. The faster the horse runs, the shorter his tail becomes. What is it?
A needle and thread.
93.84 %
41 votes

funnylogicmysteryscary

Dinner Time

A woman shoots her husband, then holds him under water for five minutes. A little while later, they both go out and enjoy a wonderful dinner together. How can this be?
She shot her husband with a camera and then developed the photo.
62.90 %
284 votes

cleanEinstein’slogic

Five houses

There is a row of five different color houses. Each house is occupied by a man of different nationality. Each man has a different pet, prefers a different drink, and smokes different brand of cigarettes. The Brit lives in the Red house. The Swede keeps dogs as pets. The Dane drinks tea. The Green house is next to the White house, on the left. The owner of the Green house drinks coffee. The person who smokes Pall Mall rears birds. The owner of the Yellow house smokes Dunhill. The man living in the centre house drinks milk. The Norwegian lives in the first house. The man who smokes Blends lives next to the one who keeps cats. The man who keeps horses lives next to the man who smokes Dunhill. The man who smokes Blue Master drinks beer. The German smokes Prince. The Norwegian lives next to the Blue house. The man who smokes Blends has a neighbour who drinks water. Who has fish at home?
German.
82.20 %
54 votes

logic

Rectangular house

A man builds a house rectangular in shape. All sides have southern exposure. A big bear walks by, what color is the bear? Why?
White. The house is at the North Pole, so the polar bear.
92.86 %
35 votes