I have Rs.50 and I spend it in the way as below.

You can take four of the five letters out of this word, but the pronunciation never changes. What is the word?

What has many keys but can’t open a single lock?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

A boy was at a carnival and went to a booth where a man said to the boy, "If I write your exact weight on this piece of paper then you have to give me $50, but if I cannot, I will pay you $50." The boy looked around and saw no scale so he agrees, thinking no matter what the carny writes he'll just say he weighs more or less. In the end the boy ended up paying the man $50. How did the man win the bet?

Can you find a number that lies one third of the distance between 1/3 and 2/3?

In case you were starting to feel confident, this one was meant for third graders in Vietnam. The answer is 66, but we don't blame you for scratching your head about how they got there.

He digs out tiny caves and stores gold and silver in them. He also built bridges of silver and made crowns of gold. They are the smallest you could imagine. Sooner or later everybody needs his help, yet many people are afraid to let him help them. Who is he?

I always drive my customer away.

Who am I?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?