When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

The first box has two white balls. The second box has two black balls. The third box has a white and a black ball.

Boxes are labeled but all labels are wrong!

You are allowed to open one box, pick one ball at random, see its colour and put it back into the box, without seeing the colour of the other ball.

How many such operations are necessary to correctly label the boxes?

Below is the sum of symbols in each row and column in the figure. Analyzing the figure, can you find out the value of the symbols?

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

Three friends decide to distribute the soda cans they had among them. When all of them had drunk four cans each, the total number of cans that remained was equal to the cans each one of them had after they had divided the cans.

Can you calculate the total number of cans before distribution?

I was speeding and ran through a stop sign, yet two traffic officers who were there do nothing about it.

why?

A man says, "Brothers and sisters, have I none, but that man's father is my father's son." Who is that man?

Every words stands for unique digit that makes the arithmetic equation true

SEVEN + SEVEN + SIX = TWENTY.

What are the digits ?

It was a dark stormy night and a couple were in a car driving madly to a city. The car broke down and the husband had to go get help from someone who spoke his language. He was afraid to leave his wife alone in the car so he locked the car before leaving. When he came back, the car was in the same state as he had left it but his wife was dead, there was blood on the floor and there was a stranger in the car. What happened?

I come in different shapes and sizes.
Parts of me are curved, other parts are straight.
You can put me anywhere you like,
but there is only one right place for me.
What am I?