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?

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

There are 3 apples in the basket and you take away 2. How many apples do you have now?

The following sentence is false. The preceding sentence is true.
Are these two sentences true or false?

I am a type of food that is often found in the fridge and can be white in colour. What I am?
Hint 1: I am a dairy product.
Hint 2: You can spread me on the bread.

How many squares, of any size, can you find on this chessboard which do not contain a Rook?

You are presented with three boxes. One of them has a red ball inside and the other two have a black ball inside each of them. You are asked to pick up the one with red ball and you pick one. Now, one of the other boxes is opened and it is found to have a black ball.

You are presented with a chance to change your box with the one that is left closed. Will you change your box? Why or why not?

What has 88 keys?

Before Balboa discovered the Pacific Ocean, which was the largest ocean before that?