document.write( "Question 944565: A student has 5 engineering books, 3 math books, and 4 chemistry books. She is to put them all onto three shelves (top, middle, lower) with each shelf containing only books of a single discipline, but the order on any particular shelf is completely free. In how many ways can she do this ?\r
\n" ); document.write( "\n" ); document.write( "I'm stuck here, it seems easy enough, but why would the number of books matter if each shelf contains one discipline and the order on each shelf doesn't matter? Am I missing something here?
\n" ); document.write( "It looks along the lines of 5!*3!*4!*3!, but not sure. \n" ); document.write( "
Algebra.Com's Answer #576755 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "No, you're right about the number of books.  The answer is just 6.\r\n" );
document.write( "Here's why.\r\n" );
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document.write( "The books of each discipline are NOT ordered, However the shelves \r\n" );
document.write( "ARE ordered (top. middle, lower)\r\n" );
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document.write( "We have some engineering books, some math books, and some chemistry books.\r\n" );
document.write( "You are right that it doesn't matter how many of each, so the 5,3, and 4 have\r\n" );
document.write( "nothing to do with the problem.  They're just to throw you off.\r\n" );
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document.write( "So the answer is just 3! or 6.\r\n" );
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document.write( "Here are the 6 ways\r\n" );
document.write( "                 1    2    3    4    5   6\r\n" );
document.write( "------------------------------------------     \r\n" );
document.write( "top shelf       5E   5E   3M   3M   4C  4C\r\n" );
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document.write( "middle shelf    3M   4C   5E   4C   5E  3M\r\n" );
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document.write( "lower shelf     4C   3M   4C   5E   3M  5E\r\n" );
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document.write( "Edwin
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