Small World Problem

Last Problem:

You are celebrating today the birthday of your two year old niece. Her birthday cake has two candles proudly place on top. When your niece attempts to blow out the two candles, she blows between them (instead of blowing them out). What happens to the flame of the candles? Do the flames move outward, inward or simply flicker?

Answer:

The stream of air creates a low pressure zone which draws the flames closer together.

Today’s Problem:

Pick any two people out of all the persons living in the United States. If you wanted to link those two persons by a chain of acquaintances (such as a friend of a friend of a friend …), how many people or connections would you need to make on average?