The Cannibals of an Island have the habit of eating each other.
One evening, the cannibals threw a dinner party. Six cannibals turned up and they decided to eat each other in turn. So someone was selected for everyone to eat (except the victim!), and when he had been eaten, someone else was selected, and so on.
If it took one cannibal two hours on his own to devour one person, how long was it before just one consumer remained?

Answer: 4.5666666667 hours

(Did you copy/paste this one from Dr. Hannibal Lector's autobiography?)

Explanation:

If 1 Cannibal eats 1 person in 2 hrs, then 1 Cannibal eats 1/2 person in 2/2 = 1 hour; he eats 1/3 of a person in 2/3 hour; 1/4 of a person in 2/4 = 1/2 hour, and 1/5 of a person in 2/5 hour.

5 Cannibals simultaneously eat 1/5 of a person in 2/5 hour. 4 Cannibals simultaneously eat 1/4 of a person in 1/2 hour. 3 Cannibals simultaneously eat 1/3 of a person in 2/3 hour. 2 Cannibals simultaneously eat 1/2 of a person in 1 hour. The last Cannibal eats 1 person in 2 hours.

2/5 + 1/2 + 2/3 + 1 + 2 = 4.5666666667 hour

Posted by Penny on 2004-02-04 09:41:16