document.write( "Question 1083149: what is r if 9Pr= 3024
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Algebra.Com's Answer #697162 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Let's compute the following ten nPr values.
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\n" ); document.write( "Let r be a whole number and let it range from r = 0 to r = 9.
\n" ); document.write( "The goal is to find which r value yields n P r = 9 P r = 3024.\r
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\n" ); document.write( "\n" ); document.write( "When r = 0, then...\r
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\n" ); document.write( "\n" ); document.write( "n P r = (n!)/((n-r)!)
\n" ); document.write( "9 P 0 (9!)/((9-0)!)
\n" ); document.write( "9 P 0 = (9!)/(9!)
\n" ); document.write( "9 P 0 = (9*8*7*6*5*4*3*2*1)/(9*8*7*6*5*4*3*2*1)
\n" ); document.write( "9 P 0 = (362880)/(362880)
\n" ); document.write( "9 P 0 = 1\r
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\n" ); document.write( "\n" ); document.write( "When r = 1, then...\r
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\n" ); document.write( "\n" ); document.write( "n P r = (n!)/((n-r)!)
\n" ); document.write( "9 P 1 (9!)/((9-1)!)
\n" ); document.write( "9 P 1 = (9!)/(8!)
\n" ); document.write( "9 P 1 = (9*8*7*6*5*4*3*2*1)/(8*7*6*5*4*3*2*1)
\n" ); document.write( "9 P 1 = (362880)/(40320)
\n" ); document.write( "9 P 1 = 9\r
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\n" ); document.write( "\n" ); document.write( "When r = 2, then...\r
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\n" ); document.write( "\n" ); document.write( "n P r = (n!)/((n-r)!)
\n" ); document.write( "9 P 2 (9!)/((9-2)!)
\n" ); document.write( "9 P 2 = (9!)/(7!)
\n" ); document.write( "9 P 2 = (9*8*7*6*5*4*3*2*1)/(7*6*5*4*3*2*1)
\n" ); document.write( "9 P 2 = (362880)/(5040)
\n" ); document.write( "9 P 2 = 72\r
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\n" ); document.write( "\n" ); document.write( "When r = 3, then...\r
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\n" ); document.write( "\n" ); document.write( "n P r = (n!)/((n-r)!)
\n" ); document.write( "9 P 3 (9!)/((9-3)!)
\n" ); document.write( "9 P 3 = (9!)/(6!)
\n" ); document.write( "9 P 3 = (9*8*7*6*5*4*3*2*1)/(6*5*4*3*2*1)
\n" ); document.write( "9 P 3 = (362880)/(720)
\n" ); document.write( "9 P 3 = 504\r
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\n" ); document.write( "\n" ); document.write( "When r = 4, then...\r
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\n" ); document.write( "\n" ); document.write( "n P r = (n!)/((n-r)!)
\n" ); document.write( "9 P 4 (9!)/((9-4)!)
\n" ); document.write( "9 P 4 = (9!)/(5!)
\n" ); document.write( "9 P 4 = (9*8*7*6*5*4*3*2*1)/(5*4*3*2*1)
\n" ); document.write( "9 P 4 = (362880)/(120)
\n" ); document.write( "9 P 4 = 3024\r
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\n" ); document.write( "\n" ); document.write( "When r = 5, then...\r
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\n" ); document.write( "\n" ); document.write( "n P r = (n!)/((n-r)!)
\n" ); document.write( "9 P 5 (9!)/((9-5)!)
\n" ); document.write( "9 P 5 = (9!)/(4!)
\n" ); document.write( "9 P 5 = (9*8*7*6*5*4*3*2*1)/(4*3*2*1)
\n" ); document.write( "9 P 5 = (362880)/(24)
\n" ); document.write( "9 P 5 = 15120\r
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\n" ); document.write( "\n" ); document.write( "When r = 6, then...\r
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\n" ); document.write( "\n" ); document.write( "n P r = (n!)/((n-r)!)
\n" ); document.write( "9 P 6 (9!)/((9-6)!)
\n" ); document.write( "9 P 6 = (9!)/(3!)
\n" ); document.write( "9 P 6 = (9*8*7*6*5*4*3*2*1)/(3*2*1)
\n" ); document.write( "9 P 6 = (362880)/(6)
\n" ); document.write( "9 P 6 = 60480\r
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\n" ); document.write( "\n" ); document.write( "When r = 7, then...\r
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\n" ); document.write( "\n" ); document.write( "n P r = (n!)/((n-r)!)
\n" ); document.write( "9 P 7 (9!)/((9-7)!)
\n" ); document.write( "9 P 7 = (9!)/(2!)
\n" ); document.write( "9 P 7 = (9*8*7*6*5*4*3*2*1)/(2*1)
\n" ); document.write( "9 P 7 = (362880)/(2)
\n" ); document.write( "9 P 7 = 181440\r
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\n" ); document.write( "\n" ); document.write( "When r = 8, then...\r
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\n" ); document.write( "\n" ); document.write( "n P r = (n!)/((n-r)!)
\n" ); document.write( "9 P 8 (9!)/((9-8)!)
\n" ); document.write( "9 P 8 = (9!)/(1!)
\n" ); document.write( "9 P 8 = (9*8*7*6*5*4*3*2*1)/(1)
\n" ); document.write( "9 P 8 = (362880)/(1)
\n" ); document.write( "9 P 8 = 362880\r
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\n" ); document.write( "\n" ); document.write( "When r = 9, then...\r
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\n" ); document.write( "\n" ); document.write( "n P r = (n!)/((n-r)!)
\n" ); document.write( "9 P 9 (9!)/((9-9)!)
\n" ); document.write( "9 P 9 = (9!)/(0!)
\n" ); document.write( "9 P 9 = (9*8*7*6*5*4*3*2*1)/(1)
\n" ); document.write( "9 P 9 = (362880)/(1)
\n" ); document.write( "9 P 9 = 362880\r
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\n" ); document.write( "\n" ); document.write( "In the work shown above, we see that 9 P 4 = 3024\r
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\n" ); document.write( "\n" ); document.write( "So if 9 P r = 3024, then r = 4\r
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\n" ); document.write( "\n" ); document.write( "Answer: 4
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