Brain Teasers & Mental Math
You have 25 horses and a track that races 5 at a time, with no stopwatch. What is the minimum number of races to find the 3 fastest horses?
Model answer
7 races.
Races 1–5: five heats of 5. Race 6: the five heat winners — its winner is the fastest horse overall.
Race 7: only five horses can still be 2nd or 3rd overall: the 2nd and 3rd from the…
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