document.write( "Question 927624: In how many ways k types of work can be assign to n workers so that everyone has exactly
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Algebra.Com's Answer #563114 by Edwin McCravy(20055)\"\" \"About 
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document.write( "Order matters, because you can think of the n workers all lined up\r\n" );
document.write( "waiting to be assigned a type of work, and it certainly matters\r\n" );
document.write( "in what order you assign the types of work in.  So we know to use \r\n" );
document.write( "permutations, not combinations.\r\n" );
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document.write( "There are k = P(k,1) ways to assign a type of work to worker #1.\r\n" );
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document.write( "For each of those k ways to assign a type of job to worker #1, \r\n" );
document.write( "there remain k-1 types of work to assign to worker #2.\r\n" );
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document.write( "So there are k(k-1) = P(k,2) ways to assign a type of work to each of \r\n" );
document.write( "workers 1 and 2.\r\n" );
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document.write( "For each of those k(k-1) = P(k,2) ways to assign a type of job to workers\r\n" );
document.write( "#1 and #2, there remain k-2 types of work to assign to worker 3.\r\n" );
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document.write( "So there are k(k-1)(k-2) = P(k,3) ways to assign a type of work to each of \r\n" );
document.write( "workers 1, 2 and 3.\r\n" );
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document.write( "So when we get down to n workers, we'll have\r\n" );
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document.write( "k(k-1)(k-2)···[x-(n-1)] = P(k,n).\r\n" );
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document.write( "That's the answer.\r\n" );
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document.write( "Edwin
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