document.write( "Question 1085414: How many terms of the sequence { } … , 18 , 13 , 8 must be taken for the series to be 426? \n" ); document.write( "

Algebra.Com's Answer #699524 by ikleyn(52790) $\"\"$ $\"About$

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document.write( "Write the sequence in the reversed order \r\n" );
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document.write( "8, 13, 18 . . . \r\n" );
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document.write( "Use the formula for the sum of the first n terms of an AP.\r\n" );
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document.write( "Your first term is 8, and your common difference is 5.\r\n" );
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document.write( "The rest is arithmetic.\r\n" );
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\n" ); document.write( "\n" ); document.write( "See introductory lessons on arithmetic progressions in this site:\r
\n" ); document.write( "\n" ); document.write( "    - Arithmetic progressions\r
\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
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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 \"Arithmetic progressions\".\r
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