Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

Two men play a dice game involving roll of two standard dice. Man X says that a 12 will be rolled first. Man Y says that two consecutive 7s will be rolled first. The men keep rolling until one of them wins.

What is the probability that X will win ?

A large container is kept in open under the rain. Every passing hour, the water collected inside the container becomes double what it was.

In ten hours, the container is filled completely. Can you calculate how long would it have taken to be filled in half?

Here is a Swiss Cross. You have to make two straight cuts in the figure so that it is divided into four congruent pieces. Also, you should be able to join these pieces into a square then. Can you accept this challenge?

What is the next number in this series?

4,12,84,3612....

If you were to put a coin into an empty bottle and then insert a cork into the neck, how could you remove the coin without taking out the cork or breaking the bottle?

I have feet, but no legs. Which animal Am I?

What's the next in the series?

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?

How many letters are in the alphabet?

Things are just as they seem, right? Well, check again.
Can you count the number of tigers in this picture ?