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Understands that when comparing percentages and proportions, one must also consider the number of cases on which those percentages are based.

How to Win at Rock-Paper-Scissors

Is there a strategy for winning this random-event game? Yes, but only until your opponent catches on.

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Matching Birthdays

An interesting and well-known riddle in the area of probability is "The Birthday Problem." You can find information about this problem in many introductory books in probability, probability and statistics, and math tricks books for laymen. This problem falls in the category of problems called counter-intuitive -- meaning that you may be surprised at the answer.

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