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Some Problems

  1. (From Martin Gardner): If Sara shouldn't, then Wanda would. It is impossible that the statements: ``Sara should,'' and ``Camille couldn't,'' can both be true at the same time. If Wanda would, then Sara should and Camille could. Therefore Camille could. Is the conclusion valid?
  2. (From Martin Gardner): In a suburban home live Abner, his wife Beryl and their three children, Cleo, Dale and Ellsworth. The time is 8 p.m. on a winter evening.
    1. If Abner is watching television, so is his wife.
    2. Either Dale or Ellsworth, or both of them, are watching television.
    3. Either Beryl or Cleo, but not both, is watching television.
    4. Dale and Cleo are either both watching or both not watching television.
    5. If Ellsworth is watching television, then Abner and Dale are also watching.
    Who is watching television and who is not?

Carl Lee
Wed Nov 18 12:16:44 EST 1998