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Recall the question from the last section. Each of the two players rolls a die, and the winner is determined by the sum of the faces:
| Player A wins when the sum is 2, 3, 4, 10, 11, or 12. |
| Player B wins when the sum is 5, 6, 7, 8, or 9. |
If this game is played many times, which player do you think will win more often, and why?
To analyze this problem effectively, we need a clear enumeration of all possible outcomes. Let's examine one scheme that is based on a familiar idea: an addition table.
Start with a two-dimensional table:
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Red Die |
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Blue Die  |
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6 |
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5 |
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6 |
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Each possible outcome for the sum of the two dice can be enumerated in this table. For example, if the outcome were (1,1), here is how you would record it:
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Red Die |
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Blue Die  |
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1 + 1 |
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This is how you would record the outcome (2,4):
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Red Die |
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Blue Die  |
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2 + 4 |
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This is how you would record the outcome (4,2):
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Red Die |
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Blue Die  |
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6 |
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1 |
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3 |
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4 + 2 |
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5 |
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6 |
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Note that the outcome (4,2) is different from the outcome (2,4).
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