document.write( "Question 1178050: The 6th term of an AP is 35 and the 13term is 77calculate S6-S4?\r
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Algebra.Com's Answer #807230 by ikleyn(52787)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "            The problem does not define the meaning of S6, S4, so I will suppose that \r
\n" ); document.write( "\n" ); document.write( "            S6 and S4 are the sums of the first 6 and the first 4 terms of the AP, respectively.\r
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document.write( "There are 13 - 6 = 7 gaps between the 13-th and 6-th terms of the AP on the number line,\r\n" );
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document.write( "so each gap is  \"%2877-35%29%2F7\" = 6 units.\r\n" );
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document.write( "Thus the common difference of the AP is  d= 6.\r\n" );
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document.write( "Now,  \"S%5B6%5D\" - \"S%5B4%5D\" = \"a%5B5%5D\" + \"a%5B6%5D\" = \"%28a%5B6%5D-d%29\" + \"a%5B6%5D\" = (35-6) + 35 = 70-6 = 64.\r\n" );
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document.write( "It is the answer to the problem's question:  \"S%5B6%5D\" - \"S%5B4%5D\" = 64.\r\n" );
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\n" ); document.write( "\n" ); document.write( "For introductory lessons on arithmetic progressions see \r
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\n" ); document.write( "\n" ); document.write( "    - The proofs of the formulas for arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Problems on arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Word problems on arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - Finding number of terms of an arithmetic progression \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
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Arithmetic progressions\".\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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\n" ); document.write( "\n" ); document.write( "into your archive and use when it is needed.\r
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