Twelve sprinters are running a heat; those with the best
Chapter 10, Problem 34(choose chapter or problem)
Twelve sprinters are running a heat; those with the best four times will advance to the finals. (a) In how many ways can this group of four be selected? (b) If the four best times will be seeded (ranked) in the finals, in how many ways can this group of four be selected and seeded?
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