document.write( "Question 932868: in an arithmetic series, the second to last term is three times the fifth term, the sum of the first eight terms equals 136, and the fourteenth term equals the twentieth minus the second term. Determine how many terms are in the arithmetic series. \n" ); document.write( "

Algebra.Com's Answer #567013 by Edwin McCravy(20056) $\"\"$ $\"About$

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in an arithmetic series, the second to last term is three times the fifth term, the sum of the first eight terms equals 136, and the fourteenth term equals the twentieth minus the second term. Determine how many terms are in the arithmetic series.
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document.write( "Use formulas\r\n" );
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\n" ); document.write( ">>the second to last term is three times the fifth term<<
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document.write( "[That's a little bit ambiguous, because \"second to last\" might be\r\n" );
document.write( "interpreted as \"second FROM the last\"; however I will interpret\r\n" );
document.write( "it as \"NEXT TO the last\"] \r\n" );
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\n" ); document.write( ">>the sum of the first eight terms equals 136<<
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\n" ); document.write( ">>and the fourteenth term equals the twentieth minus the second term.<<
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document.write( "So we have the system of equations:\r\n" );
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document.write( "Solve that by substitution and get:\r\n" );
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document.write( "There are 24 terms.\r\n" );
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document.write( "Edwin

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