What is the fastest way to double your money?

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

Do you know what I am?

A Shopkeeper collects 71 rupees in the form of 20 paisa and 25 paisa.
He collects a total of 324 coins.

Can you tell me how many number of 20-paisa and 25-paisa he got?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

You have two buckets - one holds exactly 5 gallons and the other 3 gallons. How can you measure 4 gallons of water into the 5 gallon bucket?

(Assume you have an unlimited supply of water and that there are no measurement markings of any kind on the buckets.)

A woman lives in a skyscraper thirty-six floors high and is served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

A donkey is behind another donkey
I'm behind that second donkey
But there is a whole nation behind me

It is a murder you can describe in a word.

Find the hidden panda in the image below.

Below rebus represent famous DiCaprio movie. Can you name it?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?