Fastest horses at the racetrack

Share This Riddle

FacebookTwitterGoogle+PinterestReddit

12.9k views
16 ratings
1 saves

Question: The London Racetrack needs to submit its 3 fastest horses to the Kentucky Derby out of 25 horses. However, all of their information was lost and they don't know any of the horse's times. Similarly, they all look identical so they can't remember who's fastest.

They can only race 5 horses at once, so what is the fewest number of races they can conduct to find the 3 fastest horses?

Answer: 7 races are required.

First you divide the 25 horses into 5 groups of 5. You conduct the 5 races and take all of the fastest horses in those races and have a race with them, giving you the fastest horse. Then you take the remaining 24 horses (excluding the fastest) and remove the 4th and 5th horses in the first set of 5 races (since they definitely have 3 horses faster than them), leaving you with 14 horses. Next you can remove all of the horses that were beat in the preliminary race by the horses that got 4th and 5th in the championship race, leaving you with 8 horses. Finally, you can remove the horses that remain that lost to the 3rd place horse in the final race in the preliminary race and the horse that got 3rd in the preliminary to the horse that got 2nd in the championship race, leaving you with 5 horses.

You can then run a final race where the 1st and 2nd place horses are the 2nd and 3rd fastest. Then you know the 3 fastest horses.

Riddle Discussion

Similar Riddles

1 views
6 ratings
0 saves

By jena

Question: What do you call a sad bird?

Answer: A bluebird!

Share this:FacebookTwitterGoogle+
???? (medium)

26.2k views
23 ratings
1 saves

By Alovara

Question: What can be broken but never forgotten?

Answer: A promise

Share this:FacebookTwitterGoogle+
What am I? (medium)

24.5k views
32 ratings
0 saves

By Bist

Question: People see through me, but none pass through without killing me. I can be anywhere, and can be seen double or single. What am I?

Answer: Glass

Share this:FacebookTwitterGoogle+

4.8M views
6426 ratings
34 saves

Question: What tastes better than it smells?

Answer: A tongue.

Share this:FacebookTwitterGoogle+

3.2M views
4481 ratings
23 saves

Question: What goes in the water black and comes out red?

Answer: A lobster.

Share this:FacebookTwitterGoogle+

© 2013-2014 Good Riddles Now. All rights reserved.

FacebookTwitterGoogle+RSS Feed