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A logical question

  1. Aug 14, 2008 #1
    martha wants to buy a fast and a chip car which answers to this term:
    the car should be painted in silver or a convertible ,but not both.

    which one of the following arguments will lead us to the conclusion
    that martha will not find a car which fits by her demands?
    1.a fast car which is not chip,unless its painted in silver and it a convertible
    2.a fast car painted in silver,but its not a convertible
    3.a chip car will never be painted in silver
    4.a convertible car are not fast and they are not painted in silver
  2. jcsd
  3. Aug 15, 2008 #2


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    So let's define some properties:
    F: the car is fast
    Ch: the car is cheap
    S: the car is painted silver
    Co: the car is convertible

    Now can you make a logical expression which is true when she does buy the car? So I'm looking for something of the form: (F or Ch) and (F and ((not Co) or S).
    Also try to express the answer possibilities this way (as an example, number 1 would become: [itex](F \wedge \neg Ch) \vee (S \wedge Co)[/itex]).

    Once you have that, I will of course ask you if you can negate that expression.
  4. Aug 15, 2008 #3
    I doubt the OP has experience with formal logic, let alone symbolic logic, CompuChip.
  5. Aug 15, 2008 #4


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    Is there an easier way to solve it, then?

    By the way I just noticed this is posted in "general discussion > brain teasers" so maybe the question is for us to find the answer and the OP already has it.
  6. Aug 15, 2008 #5
    i am having the final answer
    bur i dont have the way its being solved
  7. Aug 15, 2008 #6
    i think i got the way they solved it
    its 1
    because in that way the car will be silver and convertible
    which is not possible
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