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EasyCounting
#913 · Combinatorics · Counting

Watches containing a given man

Of the watches counted in part (1), how many include a particular man?

~2 minAnswer checked instantlycombinations

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. XI. Permutations and Combinations, Examples XI.a, No. 11 (part 2)

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