document.write( "Question 626467: Five students hold a checkers tournament. In the first round, each of the students plays each of the other students just once. How many different games are played? \n" ); document.write( "
Algebra.Com's Answer #394187 by Edwin McCravy(20067)\"\" \"About 
You can put this solution on YOUR website!
\r\n" );
document.write( "\"5 choose 2\", or \"the combinations of 5 things taken 2 at a time\".  It's\r\n" );
document.write( "combinations, not permutations because order is not considered since \r\n" );
document.write( "A playing B is the same thing as B playing A.\r\n" );
document.write( "\r\n" );
document.write( "C(5,2) = \"5%21%2F%282%21%2A%285-2%29%21%29\" = \"5%2A4%2A3%2A2%2A1%2F%28%282%2A1%29%283%21%29%29\" = \"5%2A4%2A3%2A2%2A1%2F%28%282%2A1%29%283%2A2%2A1%29%29\" = 10 \r\n" );
document.write( "\r\n" );
document.write( "The 10 games are:\r\n" );
document.write( "\r\n" );
document.write( "1. A and B play.\r\n" );
document.write( "2. A and C play.\r\n" );
document.write( "3. A and D play.\r\n" );
document.write( "4. A and E play.\r\n" );
document.write( "5. B and C play.\r\n" );
document.write( "6. B and D play.\r\n" );
document.write( "7. B and E play.\r\n" );
document.write( "8. C and D play.\r\n" );
document.write( "9. C and E play.\r\n" );
document.write( "10. D and E play.\r\n" );
document.write( "\r\n" );
document.write( " Edwin
\n" ); document.write( "
\n" );