document.write( "Question 1141173: Find the sum of the first 12 terms of arithmetic sequence with a common difference of -5 if its 23rd term is 556. \n" ); document.write( "
Algebra.Com's Answer #761701 by josgarithmetic(39618)\"\" \"About 
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Common Difference \"-5\" as given\r
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\n" ); document.write( "\n" ); document.write( "If first term is A, then \"A%2B%28-5%29%2823-1%29=556\"
\n" ); document.write( "A=666}}
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\n" ); document.write( "12th term is 666-5(11)=500\r
\n" ); document.write( "\n" ); document.write( "Sum asked for is (12/2)(666+500) from the summation formula for Arithmetic Series.\r
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\n" ); document.write( "\n" ); document.write( "6996 \n" ); document.write( "
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