What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

Jim and Sarah are in a long-distance relationship. Jim buys an engagement ring for Sarah and wants to mail it to her. Unfortunately, the only way to ensure the ring will be received is to place a lock on the package. Jim has locks and Sarah has locks, but neither has keys for each other’s locks. How can they make sure the ring isn’t stolen?

In a chess board, the queen piece can move horizontally, vertically and diagonally freely. The picture represents the same.Can you place 8 queens on the board in a manner that none of the queens can attack each other?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

What is 3/7 chicken, 2/3 cat and 2/4 goat?

Buy me, smell me or deliver me, I do not change.

Who am I?

You find yourself in a strange place guarded by two guards.One of the guard always say truth while other always lies.You don't know the identity of the two.You can ask only one question to go out from there. What should you ask?

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different.

How do you measure 45 minutes?

You need to move three matchsticks to form three squares. Can you do it?

In the image given, you can find several triangles. Can you count them all?