There are 25 horses. You have to get first 3 fastest horses out of all 25 by making some number of matches between them.
Rule 1: You have no gadget to count the time taken.
Rule 2: Only 5 horses can run on the track (ground) at one time.
What is the minimum number of matches you will have to conduct to choose these 3 fastest horses?
Hint 1 : Try and eliminate as many horses as possible.
Hint 2 : The horse which comes 2nd in one match can be possibly faster than the winner of 2nd match (when you divide the horses in groups of 5 and arrange matches.)