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MathNet 2009-part-05 — 172 problems (EN–VI) Question 19

Math Olympiad Vault · MathNet 2009-part-05 — 172 problems (EN–VI)

Question 19

Tanks has a pile of 5 blue cards and 5 red cards. Every morning, he takes a card and throws it down a well. What is the probability that the first card he throws down and the last card he throws down are the same color?