mjs@sfsup.UUCP (M.J.Shannon) (02/20/86)
Back in grammar school, and probably in Jr. High & High School as well, I remember solving a class of puzzles I haven't seen since. The general format was a short description of the situation, followed by several (10 to 15) statements about individual clues to the answer. For instance, there's one about 5 different colored houses, whose inhabitants were of 5 different nationalities, smoked 5 different brands of cigarettes, had 5 different kinds of pets, and drank 5 different types of liquid. The question that was to be answered was "Who drank water and who owned a zebra?" The reason I remember it even this well is that I remember how I solved it: by drawing 5 5x5 matricies, and marking the elements based on the clues given (like "The Englishman did not smoke Parliaments." or "The man in the red house drank scotch." or "The man next to the brown house was allergic to cats.", etc.). Can anyone out there in puzzle land either provide me with these sorts of puzzles or a source for same? Thanks much, -- Marty Shannon UUCP: ihnp4!attunix!mjs Phone: +1 (201) 522 6063 Disclaimer: I speak for no one. "If I never loved, I never would have cried." -- Simon & Garfunkel
lee@ukma.UUCP (Carl Lee) (02/25/86)
>Back in grammar school, and probably in Jr. High & High School as well, I >remember solving a class of puzzles I haven't seen since. The general format >was a short description of the situation, followed by several (10 to 15) >statements about individual clues to the answer. > >For instance, there's one about 5 different colored houses, whose inhabitants >were of 5 different nationalities, smoked 5 different brands of cigarettes, >had 5 different kinds of pets, and drank 5 different types of liquid. The >question that was to be answered was "Who drank water and who owned a zebra?" > >The reason I remember it even this well is that I remember how I solved it: >by drawing 5 5x5 matricies, and marking the elements based on the clues given >(like "The Englishman did not smoke Parliaments." or "The man in the red >house drank scotch." or "The man next to the brown house was allergic to >cats.", etc.). > >Can anyone out there in puzzle land either provide me with these sorts of >puzzles or a source for same? > > Thanks much, >-- > Marty Shannon >UUCP: ihnp4!attunix!mjs >Phone: +1 (201) 522 6063 I have a very small collection of such puzzles, and can also refer you to "Recreational Logic" by Martin Gardner, which is Chapter 11 in his collection entitled The 2nd Scientific American Book of Mathematical Puzzles & Diversions, Simon and Schuster, 1961. Gardner references Henry Dudeney, Puzzles and Curious Problems, problem 49, as well as Lewis Carroll. He says that "Carroll was fond of inventing quaint and enormously complicated problems of this sort. Eight are to be found in the appendix of his Symbolic Logic." Gardner includes the following problem devised by Raymond Smullyan (who has written several delightful books on logic): 1. In 1918, on the day that the armistice of World War I was signed, three married couples celebrated by having dinner together. 2. Each husband is the brother of one of the wives, and each wife is the sister of one of the husbands; that is, there are three brother-sister pairs in the group. 3. Helen is exactly 26 weeks older than her husband, who was born in August. 4. Mr. White's sister is married to Helen's brother's brother-in-law. She (Mr. White's sister) married him on her birthday, which is in January. 5. Marguerite White is not as tall as William Black. 6. Arthur's sister is prettier than Beatrice. 7. John is 50 years old. What is Mrs. Brown's first name? Other sources for such problems: George J. Summers, New Puzzles in Logical Deduction, Dover, 1968. George J. Summers, Test Your Logic, Dover, 1972. C.R. Wylie, Jr., 101 Puzzles in Thought and Logic, Dover, 1957. For those who are interested, the problem mentioned at the beginning of this note is probably isomorphic to the following: 1. There are 5 houses, each a different color and inhabited by men of different nationalities with different pets, drinks, and cigarettes. 2. The Englishman lives in the red house. 3. The Spaniard owns the dog. 4. Coffee is drunk in the green house. 5. The Ukrainian drinks tea. 6. The green house is immediately to your right of the white house. 7. The Old Gold smoker owns snails. 8. Kools are smoked in the yellow house. 9. Milk is drunk in the middle house. 10. The Norwegian lives in the first house on the left. 11. The man who smokes Chesterfields lives next to the man with the fox. 12. Kools are smoked next to the house with a horse. 13. The Lucky Stripe smoker drinks orange juice. 14. The Japanese smokes Parliament. 15. The Norwegian lives next to the blue house. Who drinks water and who owns the zebra? Carl W. Lee, Math. Dept., University of KY, Lexington