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Math Help - counting points

  1. #1
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    Exclamation counting points

    Given 6 points, no 4 of which are collinear, what is the maximum number of lines that can be represented? What is the minimum number of lines that can be represented? (Keep a graphical representation of this, as I might ask to see your diagram of the situation)

    can anyone solve this or at least tell me how to start this equation.

    thanks
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  2. #2
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    Quote Originally Posted by mdizzle12830 View Post
    Given 6 points, no 4 of which are collinear, what is the maximum number of lines that can be represented? What is the minimum number of lines that can be represented? (Keep a graphical representation of this, as I might ask to see your diagram of the situation)
    Tha maximum is when no 3 are collinear. For example, all 6 are lying on a circle. So then the number of lines that can be drawn is the number of ways selecting two points from 6 points that is _6C_2=15

    The minimum seem like the wrost case scenario. That is ,
    Code:
    *    *    *
              *
              *
    6
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  3. #3
    Senior Member OReilly's Avatar
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    Quote Originally Posted by ThePerfectHacker View Post
    Tha maximum is when no 3 are collinear. For example, all 6 are lying on a circle. So then the number of lines that can be drawn is the number of ways selecting two points from 6 points that is _6C_2=15

    The minimum seem like the wrost case scenario. That is ,
    Code:
    *    *    *
              *
              *
    6

    Your diagram of minimum lines contains only 5 points.


    Minimum lines diagram can be:
    Code:
    *    *    *
    *    *
    *
    Minimum is 9 lines.
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  4. #4
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    Quote Originally Posted by OReilly View Post
    Your diagram of minimum lines contains only 5 points.


    Minimum lines diagram can be:
    Opps, I started counting from 2.
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  5. #5
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    ????????

    i didnt really understand what you said, i really don't care how to do it, i just need the answer. thank you very much, i really appreciate it.
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