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Subject: "J. A. H. Hunter's "Fun With Figures""     Previous Topic | Next Topic
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Joel Shapiro
Sep-10-06, 06:36 AM (EST)
"J. A. H. Hunter's "Fun With Figures""
   When I was a youngster in the 1960's, our local newspaper published a weekly math puzzle by one J. A. H. Hunter. Once per month the puzzle was of this type: Given four digits, use only those digits in any order with any mathematical operations you like (except factorial) to make an expression for each positive integer in turn. For example: given the digits 3578: 5+7-8-3 = 1; (5-3)x(8-7) = 2; 8+5-7-3 = 3; and so on. Eventually you would hit'some integer for which it was impossible to form an expression using just these four digits. One could use the basic operations + - x and /, parentheses, roots and powers, just not the factorial sign.

I collected these puzzles over a period of several years and would like to see them again. Does anyone remember these puzzles and perhaps have a book or list of them? Is there a way to determine in advance what the first impossible solution is for any given set of four digits?

Please email me at ijshapiro@sympatico.ca if you can help. Thanks.

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Rob Fatland
Sep-29-06, 09:22 PM (EST)
1. "RE: J. A. H. Hunter's "Fun With Figures""
In response to message #0
   A related card game called "24":
4 players, remove all face cards, deal the remaining 40 cards face down to the players. Game proceeds in rounds, objective is to be the first to get rid of all cards in your hand.
A round: Each player simultaneously flips their top card into the center so four random cards with values 1--10 are visible face up.
The objective is to use + - x / and any necessary parentheses to arrive at 24. At any point after face-up each player may say "Got it!" Once three of the four have said "Got it!" the fourth person chooses one of them to demonstrate a proof. If the chosen person fails to do this immediately, all four cards go face down to the bottom of his hand. If he succeeds, the fourth person (the last to get 24) receives the cards. In some cases (say 4 aces) it will be impossible to reach 24. After a time if all players agree the four cards are returned randomly to their hands.

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