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This might be off topic but i need help with this math problem

  1. Nov 28, 2007 #1
    Die A has four 9's and two 0's on its faces. Die B has four 3's and two 11's on its faces. when either of these dice is rolled, each face has an equal chance of landng on top. two players are going to play a game. the first player selects a die and rolls it. the second player rolls the remaining die. the winner is the player whose die has the higher number on top.

    A) suppose you are the first player and you want to win the game. which die would you select and why

    B) Suppose the player using die A receives 45 tokens each time he or she wins the game. how many tokens must the player using die B receive each time he or she wins in order for this to be a fair game?

    i really dont know how to start this. for a, i would think that, logically, die B would be better to choose but i dont know how to prove that statistically (even if it's right in the first place)[/FONT]
  2. jcsd
  3. Nov 28, 2007 #2
    You should count:
    (1) How many total outcomes are there? (Pretend that each of the faces on both dice are colored, so that they're different. For example die A has red 9, blue 9, green 9, purple 9, yellow 0, white 0.)
    (2) In how many cases does Die A win? In how many cases does Die B win?
    After this you should be able to compute the probabilities of winning with either die.

    Now for part (B), you need to calculate the expected value. Do you know the definition of expected value? If so, this should be easy after you finished steps (1) and (2) as I suggested.
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