Interesting Maths

Tasks

1

• Yesterday I was 17 years old, today I am 18. Next year I’ll be 20. How can it happen?

2

• I have 3 sacks of gold. In one bag there are golden sticks of 1 kg, in the other there are also golden sticks of 1 kg, but in the third there are false golden sticks of 1,1 kg. I have a digital scale which can measure only once. How do I know which bag contains the false golden sticks?

3

• On an island 10 Mathematician lions live. Their caretaker throws one slice of meat to them. If a lion eats it, it becomes a slice of meat until sunset, so the other lions can eat him. If a lion doesn’t eat meat for one day, he dies.

What will the caretaker experience the next day on the island?

4

• Two shepherds, John and Peter meet. John says to Peter: „Give me 1 sheep and I’ll have twice as much sheep than you”. Peter answered: „No, it’s better if you give me 1 sheep. This way we’ll have equal number of sheep”.

How much sheep do they both have?

5

• When the king sleeps everything he believes to be true is false. (So in other words during sleeping everything is false.) Howerer, what he believes when he’s awake is true.

Last night he believed that he and the queen had been asleep.

Was the queen sleeping?

6

Two Indians were sitting at the riverbank.

• One says: „Little Wind, your are my son!”• The other answers: „Fast Eagle, you are not my

father!”• How can it be true?

7

• A man has a birthday.

• He is asked: „Do you remember what you did 1 year ago?”

• He answers: „Yes, I can remember quite well. I was on the Arctic in my ice hut and I could see the sunrise.”

When is his birthday?