document.write( "Question 1178674: The sixth and eighth terms of an arithmetic sequence are
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Algebra.Com's Answer #808018 by ikleyn(52794) $\"\"$ $\"About$

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document.write( "The 6th and the 8th terms represent the points -11 and -19 on the number line with the difference of 8 units between them.\r\n" );
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document.write( "There are two gaps of equal length between the 6th and the 8th terms of the AP on the number line.\r\n" );
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document.write( "Hence, the length of each gap is   = 4.\r\n" );
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document.write( "    Since the given AP is decreasing sequence, it implies that the common difference of the AP is -4.\r\n" );
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document.write( "The 15th term is in 7 gaps distance from the 8th term;  hence\r\n" );
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document.write( "     =  - 7*4 = -19 - 28 = -47.\r\n" );
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document.write( "ANSWER.   = -47.\r\n" );
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\n" ); document.write( "\n" ); document.write( "From my post, learn how to solve such problem straightforward in short mode.\r
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\n" ); document.write( "\n" ); document.write( "My lessons on arithmetic progressions in this site are\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
\n" ); document.write( "\n" ); document.write( "    - Chocolate bars and arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - Free fall and arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Uniformly accelerated motions and arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - Increments of a quadratic function form an arithmetic progression\r
\n" ); document.write( "\n" ); document.write( "    - One characteristic property of arithmetic progressions\r
\n" ); document.write( "\n" ); document.write( "    - Solved problems on arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Calculating partial sums of arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Finding number of terms of an arithmetic progression \r
\n" ); document.write( "\n" ); document.write( "    - Inserting arithmetic means between given numbers \r
\n" ); document.write( "\n" ); document.write( "    - Advanced problems on arithmetic progressions \r
\n" ); document.write( "\n" ); document.write( "    - Problems on arithmetic progressions solved MENTALLY \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
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