In my country we only have 5, 10 and 50 cent coins. I go to a haberdashery to buy cloth to make me a dress and the saleswoman warns me that she has no change. I have six coins with which I can buy a meter of cloth or three meters but not two.
How much does each meter of fabric cost?
I have 70 cents in my pocket in two coins of 10 and one of 50 and each meter of cloth costs 20 cents.