25 horses
Definition · Level 11 · Interview practice
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Finding the fastest 3 of 25 with five-horse races and no timer takes 7 races: 5 heats, a race of heat winners, then one race for the 5 horses still in contention.
Example
Race 7: 2nd and 3rd of the champion’s heat, the 2nd winner and its runner-up, the 3rd winner.
Where Tradecraft teaches it
Level 11 · Interview practice, in the lesson “Brainteasers: the classic set”: Crisp answers and one-line reasons for the puzzles interviewers ask most.
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