document.write( "Question 1164375: I do understand the relationship between nPr and nCr {( nPr = r!(nCr) } and all. But I am missing something with the following that obviously should be apparent!\r
\n" ); document.write( "\n" ); document.write( "How does (nP5) translate into nP4 X (n-4) in the following expression given in the book:
\n" ); document.write( "30(nP5/5!) = [30 X nP4 X (n-4)] / 5!\r
\n" ); document.write( "\n" ); document.write( "Can somebody show me the intermediate steps...just with the translation of nP5 to as nP4 X (n-4)\r
\n" ); document.write( "\n" ); document.write( "Also I am new to this site. How do I insert subscripts in the equations while posting the questions?\r
\n" ); document.write( "\n" ); document.write( "Thank you \n" ); document.write( "
Algebra.Com's Answer #788755 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Must be a misprint.  They aren't equal:\r\n" );
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document.write( "\"30%28%22nP5%22%2F5%21%29+=+%2830%2A%22nP4%22%2A%28n-4%29%29%2F5%21\"\r\n" );
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document.write( "By definition:\r\n" );
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document.write( "\"%22nP5%22+=+n%28n-1%29%28n-2%29%28n-3%29%28n-4%29%28n-5%29\"\r\n" );
document.write( "\"%22nP4%22+=+n%28n-1%29%28n-2%29%28n-3%29%28n-4%29\"\r\n" );
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document.write( "So nP5 just has one more factor, (n-5), than nP4 has,\r\n" );
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document.write( "So nP5 = (n+5)nP4.\r\n" );
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document.write( "The misprint in your book was that the (n-4) on the right should have been (n-5).\r\n" );
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document.write( "Books have typos sometimes.\r\n" );
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document.write( "Edwin
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