Suppose someone comes onto the site and is bored. That person starts spreading the rumor that levik is a monkey at exactly noon (on day 1) by sending an e-mail to one random person.
Then, each person sends an e-mail about this rumor (at exactly noon, on day 2) to one person. They can send it to anyone on perplexus (but themselves), even if that person already knows the rumor, or even if it was the person who told them about it.
Each successive day at noon, everyone that knows about the rumor sends a message to one other random person.
On average, on what day will everyone know about the rumor if there are 40 people (including the one that spread the rumor initially) at perplexus while the rumor is still spreading?
What if there were x people at perplexus while the rumor is still spreading?
This sequence was first described by Leonardo of Pisa, who was known as Fibonacci (ca. 1200), to describe the growth of a rabbit population. Gamer changed rabbits to rumors in order to disguise his source. But that's where this puzzle must have come from.
Edited on May 1, 2004, 6:15 am
Posted by Penny
on 2004-05-01 03:55:47