Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.

What does this rebus mean?

O
N
C
E
TIME

Can you make a fire with just a single stick?

Can you find out the number of the parking space in which the car is parked?

A horse was tied to a rope 5 meters long and the horses food was 15 meters away from the horse. How did the horse reach the food?

There is a brick of gold and a brick of iron in a boat (both 10-inch blocks), if they are both dropped into the water which will make the water level higher?

81 x 9 = 801. What must you do to make the this equation true?

Rectify the following equality 101 - 102 = 1 by moving just one digit.

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?

They are three errirs in this question. Can you find them?