document.write( "Question 1162098: Find the total number of different 4-digit numbers using all the digits in the number 4129.\r
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Algebra.Com's Answer #785832 by ikleyn(52798)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "It is the number of all permutations of four digits, which is 4*3*2*1 = 24.        ANSWER  \r\n" );
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document.write( "Another way to present it is to say that\r\n" );
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document.write( "    - any one of four digits can occupy the 1-st position;\r\n" );
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document.write( "    - any one of the remaining three digits can occupy the 2-nd position;\r\n" );
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document.write( "    - any one of the remaining two digits can occupy the 3-rd position;\r\n" );
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document.write( "    - and there is only one way to fill the last, 4-th position,\r\n" );
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document.write( "which gives you  4*3*2*1 options, in all.\r\n" );
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\n" ); document.write( "\n" ); document.write( "On Permutations, see these introductory lessons\r
\n" ); document.write( "\n" ); document.write( "    - Introduction to Permutations\r
\n" ); document.write( "\n" ); document.write( "    - PROOF of the formula on the number of Permutations\r
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\n" ); document.write( "\n" ); document.write( "Also,  you have this free of charge online textbook in ALGEBRA-II in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic  \"Combinatorics: Combinations and permutations\". \r
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\n" ); document.write( "\n" ); document.write( "Save the link to this textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-II
\n" ); document.write( "https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson\r
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