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- (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?
- (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.
- If Abner is watching television, so is his wife.
- Either Dale or Ellsworth, or both of them, are watching
television.
- Either Beryl or Cleo, but not both, is watching television.
- Dale and Cleo are either both watching or both not watching
television.
- 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