Counting and complements · Home · difficulty 3 of 5
Grab a matching pair
A drawer holds 5 pairs of socks, every pair different, so 10 socks in all. In the dark you grab 4 socks at random, without replacement. What is the probability that at least two of them form a matching pair?
Answer with a probability. First lock in a gut guess with an 80% range, then solve it properly, then watch a simulation settle on the truth.
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