Replace the question mark with the correct number.

2 + 2= 4
3 + 3= 18
4 + 4= 48
5 + 5= ?

13 decks of cards have been mixed. What is the minimum number of cards that must be taken out from the above-mixed cards to guarantee at least one 'four of a kind?

John was piloting a plane behind a car but was never able to overtake it. Why?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

A container contains 100 eggs. They can be either fresh or rotten. What is sure is the fact that there is at least one fresh egg in that container.

If you are asked to pick two eggs randomly from the container, at least one of them will be rotten.

Can you calculate how many eggs in that container are fresh?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

Count the number of squares in the picture below.

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?