### Riddles and Puzzles

- 1 - Logical book

There are books on the shelves of my office. The one about Logic is the fourth from the left and the sixth from the right.
How many books are there on the shelve ?

- 2 - Bottle of wine

A bottle of wine and its cork weight together 110g . The bottle weight 100g more than the cork.
How much does the bottle and the cork weight?

- 3 - Water-lilies

A very strange variety of water-lilies has the ability to double the surface it occupies on a lake everyday. We planted a water-lily on a lake and it took 237 days for water-lilies to cover half of the lake.
How many days would it take for two water-lilies to cover the same surface of the lake ?

- 4 - Le Louvres

Someone has stolen the Joconde painting from Le Louvres. The inspector arrested three suspects. He knows John always lies, Thomas always says the truth and Stefan sometimes lies and some says the truth:
• John says "Hey man, I did it, piece of cake !"
• Thomas says "It cannot be Stefan."
• Stefan says "It can only be a criminal venture of John"
Who did it ?

It is at the front of the garden, and you use it a lot with eggs,
You will find one by the end of every morning,
But strangely enough, you'll never find one in a year.
What is it ?

- 6 - Choose to be free

Two old men are sitting in front of two doors. One doors leads to freedom the other one leads to jail. The two men know the secret of the doors. One of the men is always lying the other one is always telling the truth. You can ask only one question to one man before deciding which door you will go through...

- 7 - Starving worm

I had just received a dictionary divided in seven volumes. Each one of the volumes has 1000 pages of a total thickness of 30 millimeters. They are leather bound with a back cover and a front cover of 3 millimeters thickness each. I arranged them in alphabetic order on a shelve in my office. Unfortunately while I was on holidays, a worm attacked the first page of the first volume and went straight to the last page of the last volume, drilling a neat cylindrical hole in my beautiful dictionary collection.
What thickness of pages and leather cover did it go through?

A rope ladder is hanging by the side of a boat anchored in a seaport. Its bars are spaced out of 30 centimeters. The lower bar is touching water, the tide is rising 10 centimeters per hour.
How long will it take for the water to reach the next bar?

- 9 - Logic of life

A man sentenced to death is proposed the following choice "In order to choose your death. You will say a sentence. If this sentence is true you will be electrocuted. If it is false you will be poisoned." The man smiles, and says his sentence. He is still alive and will never be killed...
What did he said ?.

- 10 - Too much drinking

Three guys are going out of a Pub. Only two of them drank beer, only two of them drank wine and only two of them drank water. If a guy did not drink wine he did not drink water either. If a guy did not drink beer he did not drink wine either.
Who drank what ?

- 11 - Shopping

Two shops are facing each other on the same road and they sell the same goods. However they are not competing. ?
How can it be ?

- 12 - Hunting

Two fathers are hunting with one of their sons. Every hunter kills one rabbit. When they come back home they have three rabbits.
How is it possible ?

- 13 - Speed is relative

A very rich man refuses to split his fortune between his two sons. He says "I will give my fortune to the one whose horse will arrive LAST at the other end of the park." Surprisingly one of his sons jumps on a horse and runs as FAST as he can to the other end of the park.
Is he mad or what ?

- 14 - Time passes quickly

We are in 1999. The day before yesterday I was 32 years old, but next year I will be 35 !
When is my birthday ?
What's the date of today (date at which this sentence was true)?

- 15 - Moving office

You are moving office. You would like to be behind Elisabeth. But Elisabeth wants to be behind you.
Is there a solution ?

- 16 - Four Belgians

Three Belgians have one brother in common. One day this brother dies and the three Belgians have no brother at all...
What happened ?

- 17 - Wooden board

Is it possible to cut a square wooden board into eight identical pieces in three cuts ?

- 18 - Children

Steven and Mary had five children (yes five). Half of them are girls, how is it possible ?

- 19 - Book of lies

I have a book with 1 000 pages.
On the first page is writen : In this book there is exactly one page on which is writen a false statement.
On the second page is writen : In this book there are exactly two pages on which is writen a false statement.
On the third page is writen : In this book there are exactly three pages on which is writen a false statement.
...
On the 1 000th page is writen : In this book there are exactly 1 000 pages on which is writen a false statement.
Could there be a page saying the truth?