Long ago, in a village somewhere in the Indian subcontinent there lived a poor farmer with his young daughter. life was hard and it was getting harder due to the debts and bad  harvest. a money-lender used to give loans to the farmer, which were never paid back by him. so, the money-lender has an offer for the farmer:
“If your daughter marries me, I will clear all your debts and give you back all your land in my possesion”.
“NO WAY”,said the daughter. whole village knew how cruel this clever old bastard was, they had heard of many girls who were victims of his cruelity.
“let’s play a game then.”,said the money-lender. “I have with me a bag filled with black and white pebbles. the girl takes out a pebble from the bag, not looking into it. if it’s white, the girl and farmer is free from my claws .but if , it’s black, you have to as I say.”
they have no choice but to play this. the girl, is brilliant and sharp, notices that the money-lender’s bag has only black pebbles.the venue was the middle of a road from where the pebbles were collected. the result, as I know, the poor family were free from old-fool’s treachery. How was she able to get away with it?