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Four tires to mount on a car these can be mounted

  1. Apr 19, 2005 #1
    If you have four tires to mount on a car these can be mounted in 4!=24 different ways. I initially thought it would be 4*4=16 ways. Why is this assumption wrong? What would the problem have to be like for my 4*4 to be the solution?
  2. jcsd
  3. Apr 19, 2005 #2
    Four different tires can be mounted in 4! ways because you have 4 possibilities for the first wheel, then only 3 for the second wheel (since the tire you put on the first wheel can't be put on the second wheel) then only 2 possibilities for the third one and then only 1 for the last.

    An example of 4 * 4 = 16 ways is if you have 4 different types of tires and large numbers of each type, and a two-wheeled vehicle, then you have 4*4 = 16 different ways to choose your tires.
  4. Apr 19, 2005 #3
    Hmm....if I have four brands of tires, that would explain the first 4-digit, but how come the vehicle has to be two wheeled...? If the vehicle had three wheels, would the answer then be 4*4*4 ?
  5. Apr 19, 2005 #4
    Yes-four possibilities for the type of each tire, so you multiply them together. 4*4 for a two-wheeled vehicle, 4*4*4 for a three-wheeled vehicle.
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