Replace the question mark with the number below given a simple math problem.

You are stuck on an island where you have nothing. You find four pieces of paper somewhere on the island. What will be your strategy to escape from the island safely?

PS: No other resource is available to you on the island, neither can you build anything.

In the given figure, you can see that four match sticks are used to form a square. Can you form five squares by using six matches?

Jigsaw captured 100 people and make them stand in a circle and all these people are labelled as Person1, Person2, Person3... Person100. He made them play a crazy game in which Person 1 shot Person 2 and pass the gun to the next person and so on until one stands alive.

Which person will survive in the end?

In the attached figure, you can see a chessboard and two rooks placed on the chess board. What you have to find is the number of squares that do not contain the rooks. How many are there?

A prisoner is told: "If you tell a lie, we will hang you and if you tell the truth, we will shoot you." What did the prisoner say to save himself?

Why is it very easy to weigh a fish?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

People put me on the table and cut me but do not eat me. What am I?

Can you place six X (crosses) in below board without making three in a row in any way ?