document.write( "Question 817762: There are 9 arithmetic means between 11 and 51. The sum of the progression is \n" ); document.write( "
Algebra.Com's Answer #492176 by Edwin McCravy(20056)\"\" \"About 
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document.write( "There are 9 arithmetic means between 11 and 51. The sum of the progression is\r\n" );
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document.write( "11, _, _, _, _, _, _, _, _, _, 51\r\n" );
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document.write( "Notice with 9 terms between them, that \r\n" );
document.write( "gives a sequence of 11 terms, counting \r\n" );
document.write( "the 9 and the 51, so n=11, a1=11,\r\n" );
document.write( "a11 = 51.  (There are two elevens, \r\n" );
document.write( "so don't get them mixed up :). \r\n" );
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document.write( "If we use this sum formula, we don't need d:\r\n" );
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document.write( "Sn = \"n%2F2\"(a1 + an)\r\n" );
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document.write( "S11 = \"11%2F2\"(11 + 51)\r\n" );
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document.write( "S11 = \"11%2F2\"(62)\r\n" );
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document.write( "S11 = 341\r\n" );
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document.write( "Edwin
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