Math Is Fun Forum
  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#1 2017-04-09 16:14:30

Registered: 2012-04-29
Posts: 1,917

Conbinatorics Enigma

In a sports league, there are 20 total teams, divided into 4 divisions of 5 teams each. Over the course of a season, each team plays each of the other teams in its own division 3 times, and each of the other teams in the other divisions twice. How many games does the league have in a complete season?

I said 348 games(12*4)+(150+100+50)=348
(the a.p of 150,100, and 50 comes from a team playing the other divisions twice multiplied by 5(there are 5 teams within each division)
The official solution says 420.
Is it possible to derive 420 utilizing a method similar to mine?

The integral of hope is reality.
May bobbym have a wonderful time in the pearly gates of heaven.
He will be sorely missed.


#2 2017-04-09 20:08:16

From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Conbinatorics Enigma


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.


Board footer

Powered by FluxBB