Horse racing Problems

Problem:

There are 25 horses, but there are only five runways, that is, each game can only run five horses together, no timer, so at least a few games need to be held to determine the top three?

Analysis:

First, divide 25 horses into five groups A, B, C, D, and E. Each group runs once to determine the ranking of each group;5 required.

Hypothesis:

A1> A2> A3> A4> A5
B1> B2> B3> B4> B5
C1> c2> C3> C4> C5
D1> D2> D3> D4> D5
E1> E2> E3> E4> E5

That is:

Then, A1, B1, C1, D1, E11 gameFor example, A1> B1> C1> d1> E1.

Now that the first place has been determined as A1, we need to determine the second and third places.

As shown in, obviously, the second name must be one of A2 and B1, and the third name must be one of A2, B1, A3, B2, and C1.

Just put the five horses1 runTo determine the second and third places.

To sum up, A total of 5 + 1 + 1 = 7 games are required to determine the top three.