document.write( "Question 1093145: In how many ways can you line up 5 persons to get up a bus \n" ); document.write( "
Algebra.Com's Answer #707751 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "We can pick the 1st person as any of the 5 persons.\r\n" );
document.write( "That's 5 ways to pick the first person.\r\n" );
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document.write( "For each of those 5 ways to pick the 1st person,\r\n" );
document.write( "we can pick the 2nd person as any of the 4 remaining\r\n" );
document.write( "unpicked persons.\r\n" );
document.write( "That's 5*4 or 20 ways to pick the first two people.\r\n" );
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document.write( "For each of those 5*4 or 20 ways to pick the first two\r\n" );
document.write( "persons,\r\n" );
document.write( "we can pick the 3rd person as any of the 3 remaining\r\n" );
document.write( "unpicked persons.\r\n" );
document.write( "That's 5*4*3 or 60 ways to pick the first three people. \r\n" );
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document.write( "For each of those 5*4*3 or 60 ways to pick the first three\r\n" );
document.write( "persons,\r\n" );
document.write( "we can pick the 4th person as any of the 2 remaining\r\n" );
document.write( "unpicked persons.\r\n" );
document.write( "That's 5*4*3*2 or 120 ways to pick the first four people.\r\n" );
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document.write( "For each of those 5*4*3*2 or 120 ways to pick the first four\r\n" );
document.write( "persons,\r\n" );
document.write( "we can only pick the 5th person as the 1 remaining\r\n" );
document.write( "unpicked person.\r\n" );
document.write( "That's 5*4*3*2*1 or 120 ways to pick the five people.\r\n" );
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document.write( "Notice that 5*4*3*2*1 = 120 = 5!, read \"five factorial\".\r\n" );
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document.write( "Edwin
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