document.write( "Question 903922: A boat has 8 crew members,3 of whom can row only on one side and 2 only on the other side. Find the number of ways in which the crew can be arranged.
\n" );
document.write( " \n" );
document.write( "
Algebra.Com's Answer #548462 by Edwin McCravy(20055)![]() ![]() You can put this solution on YOUR website! \r\n" ); document.write( "Let the 8 crew members be\r\n" ); document.write( "\r\n" ); document.write( "{L1,L2,L3,R1,R2,E1,E2,E3}\r\n" ); document.write( "\r\n" ); document.write( "where the 3 L's can only row on the left side, the 2 R's\r\n" ); document.write( "can only row on the right side, and the 3 E's can row on\r\n" ); document.write( "either side.\r\n" ); document.write( "\r\n" ); document.write( "Since all three L's must row on the left, we only need to choose\r\n" ); document.write( "1 of the E's to row on the left. \r\n" ); document.write( "\r\n" ); document.write( "We can choose this E any of 3 ways.\r\n" ); document.write( "\r\n" ); document.write( "The other 4 crew members will row on the right side. \r\n" ); document.write( "\r\n" ); document.write( "For each of those 3 ways to choose the fourth crew member for\r\n" ); document.write( "the left side, there are 4! ways to arrange the 4 crew members on\r\n" ); document.write( "the left side, and 4! ways to arrange the 4 crew members on the\r\n" ); document.write( "right side.\r\n" ); document.write( "\r\n" ); document.write( "Answer 3*4!*4! = 3*24*24 = 1728 ways.\r\n" ); document.write( "\r\n" ); document.write( "Edwin\n" ); document.write( " |