Stats question help please

Discussion in 'General Discussions' started by Slurpee, Dec 14, 2010.

  1. Slurpee

    Slurpee Level II

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    Amy and Bruce are playing a game where a player wins as soon as s/he has two points more than his/her opponent. Both players start at par, and points are earned one at a time. If Amy has a 5/6 chance of winning each point, what is the probability that she will win the game? Give your answer as a fraction reduced to lowest terms.

    ^can somebody pm me or post the answer to that please? I can throw in a free neopets 4 month+ shell if you do. Show your work aswell
     
  2. Commy

    Commy Moderator
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  3. umk

    umk Newbie

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    I'm a little rusty but let me give this a try...


    b(2; 2, 5/6) = 2C2 * (5/6)2 * (1 - 5/6)2-2
    = ((2 * (2-1)) / 2!) * 25/36 * (1/6)0
    = ((2 * 1) / (2 *1)) * 25/36 * 1
    = (2 / 2) * 25/36
    = 25/36


    Can someone double check for me?
     
  4. number460

    number460 Level I

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    Yep, the answer is 25/36.

    Amy 5/6 chance
    Ben 1/6 chance

    So (5/6 * 5/6) because you are looking at the chance Amy will win the game. That is 25/36. (Of course, you have to count in the chance that it still draw after 2 Rounds [1/6 * 5/6] + [5/6 * 1/6] = 5/18. But if it's draw, the game is back to where it started and you go play another 2 rounds.

    Amy: 25/36
    Draw: 10/36
    Ben: 1/36