document.write( "Question 898542: In a geometric series, the sum of the first three terms is 304, and the sum of the first six terms is 1330. Find the sum of the first seven terms. \n" ); document.write( "

Algebra.Com's Answer #544886 by Edwin McCravy(20056) $\"\"$ $\"About$

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In a geometric series, the sum of the first three terms is 304,
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\n" ); document.write( "and the sum of the first six terms is 1330.
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document.write( "So the sum of the 3rd, 4th and 5th terms only is 1330-304 = 1026\r\n" );
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document.write( "Dividing equals by equals, equation (2) by equation (1)\r\n" );
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document.write( "Taking cube roots of both sides\r\n" );
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document.write( "Substitute in equation (1)\r\n" );
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document.write( "Multiply the terms in the parentheses and the right side by 4\r\n" );
document.write( "to clear of fractions:\r\n" );
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document.write( "Divide both sides by 19\r\n" );
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\n" ); document.write( "Find the sum of the first seven terms.
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document.write( "Multiply the top out, the 16 goes into the 128 2 times,\r\n" );
document.write( "and write the 1 on the bottom as \r\n" );
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document.write( "Multiply top and bottom by 2\r\n" );
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document.write( "Edwin

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