Count face pairs
Die A has faces 2, 2, 4, 4, 9, 9. Die B has 1, 1, 6, 6, 8, 8. Their 36 ordered face pairs are equally likely. A wins 4 + 4 + 12 = 20 of them, so A beats B with probability 20/36 = 5/9.
Discover why a die can beat one rival and lose to another.
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First lesson in this subject: Count equally likely outcomes
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Die A has faces 2, 2, 4, 4, 9, 9. Die B has 1, 1, 6, 6, 8, 8. Their 36 ordered face pairs are equally likely. A wins 4 + 4 + 12 = 20 of them, so A beats B with probability 20/36 = 5/9.
You are reading the opening. Members read every lesson and guide in full. A free account reads the first lesson in each subject in full.
You are reading the opening. Your free account reads the first lesson in each subject in full. Members read every lesson and guide in full.
First lesson in this subject: Count equally likely outcomes
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Practice · Find dice that beat one another in a cycle, then test how rolling twice changes the best response.
Book · Count outcomes, update chances with new information, and compare decisions through worked examples.
Previous lesson · Track both patterns on one sequence and count unfinished races.
Next lesson · Build the distribution of sums before choosing a counter to an opponent.
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