## March 6, 2008

### Horse puzzles

There are 25 horses. In each race only 5 horses
can participate.How many races are required to select
best 5 horses out of 25?

rose said...

5 races are sufficient

Anonymous said...

If you have some method of timing the horses, then 5 is enough. Otherwise you have to race 5 then replace the one which runs last with a new horse and race them again, each time substituting a new horse for the one that runs last. After 21 races you will have the four fastest horses.

You must then run thru this same process to determine which of the remaining 21 horses is the fastest (to fill the 5th pos'n). Like before, race 5 and replace the 4 slowest with 4 new horses. After 5 races you will have the fastest of the remaining 21.

So, 26 in total.

Secret SquÃ¯rrel

s.arun said...

7 races are enough you have to make race for five sets of five each in five races select all the winners and make them run 6th race and then compare the remaining which have the chance of coming in best five in the last race 7 chances are enough

satish said...

5

Anonymous said...

9 races

Dev said...

5

Anonymous said...

14 races r required , 6 to determine the first winner, then 2 races to determine the next and so on

Sasi said...

10 races are enough.
after first 5 races, select winners of initial 5 races to determine fastest and repalce it from its group which came next in initial race to determine next fastest, so total 10 races

rishu said...

9 races are enough.

Anonymous said...

Here is a nice puzzle for u all: A has 5 breads, B has 3 breads. C has no breads, and all 3 ate breads equally. Then C paid A & B \$8 and left. How these \$8 should be distributed fairly to A & B?