document.write( "Question 1137607: Find the sum of the arithmetic sequence: 56, 58, 60, 62, …, 78 \n" ); document.write( "

Algebra.Com's Answer #755464 by josgarithmetic(39620) $\"\"$ $\"About$

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General term of sequence, $\"56%2B%28n-1%29%2A2\"$ ;\r
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\n" ); document.write( "\n" ); document.write( "78 is at index $\"56%2B2%28n-1%29=78\"$
\n" ); document.write( " $\"2n-2=78-56\"$
\n" ); document.write( " $\"2n=78-56%2B2\"$
\n" ); document.write( " $\"n=12\"$ \r
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\n" ); document.write( "\n" ); document.write( "Sequence is 12 terms in length.\r
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\n" ); document.write( "\n" ); document.write( "SUM:
\n" ); document.write( " $\"highlight_green%28%2812%2F2%29%2856%2B78%29%29\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"804\"$ \n" ); document.write( "

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