
A long time ago (around 1974) when I was in high school, I learned a logic
game called Bagels. The board game Mastermind uses
very similar rules, but you don't need any props to play this game.
This game was developed by Lawrence Hall of Science and Math in Berkeley
and is documented in the book named
Family Math.
The game is deceptively simple. If you play well though,
it can be fairly deep.
Do you want to take the role of
choosing a number
or guessing my number?
Rules:
 There are two opponents. One picks a number, and the other one
attempts to guess the number. The person picking the number must
give accurate answers to the guesses.
 The person picking a number picks a three digit number.
In this version, there may be no leading zeros, and digits
may not be repeated.
 The person guessing the number gives three digit numbers.
 The person who picked the number answers:
 Fermi  One of the digits in the guess matches
one of the digits in the answer, and it is in the right
position.
 Pico  One of the digits in the guess matches
one of the digits in the answer, but the digit is not
in the right place.
 Bagels  None of the digits in the guess match
any of the digits in the answer.
Multiple answers may come out of a single guess. For examples,
look at the table below:
Picked Number  Guess  Answer 
123  456  Bagels  None of the digits match. 
123  345  Pico  The 3 matches, but is in the wrong place. 
123  543  Fermi  The 3 matches, and is in the right place. 
123  321  Pico Pico Fermi  The 3 and
1 match, but are in the wrong place, and the 2 matches
and is in the right place. 
 Players take turns holding each role.
The one who averages the fewest guesses is the better player.

