document.write( "Question 1173259: From the numbers 1,2,3,4,5,6,7,8, and 9, four different numbers are selected to form a four-digit number.\r
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Algebra.Com's Answer #798468 by ikleyn(52786)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "If repeating is allowed, the answer is  9*9*9*9 = \"9%5E4\" = 6561  possible numbers.\r\n" );
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document.write( "If repeating is not allowed, then the answer is 9*8*7*6 = 3024 possible numbers.\r\n" );
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\n" ); document.write( "\n" ); document.write( "If you want to see many similar solved problems on PERMUTATIONS, see my 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
\n" ); document.write( "\n" ); document.write( "    - Simple and simplest problems on permutations\r
\n" ); document.write( "\n" ); document.write( "    - Special type permutations problems \r
\n" ); document.write( "\n" ); document.write( "    - Problems on Permutations with restrictions \r
\n" ); document.write( "\n" ); document.write( "    - OVERVIEW of lessons on Permutations and Combinations\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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