document.write( "Question 1200343: For which values of n is the terms value equal to the sum of the terms to that point in the
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Algebra.Com's Answer #834450 by ikleyn(52788) $\"\"$ $\"About$

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\n" ); document.write( "For which values of n is the terms value equal to the sum of the terms to that point in the
\n" ); document.write( "the arithmetic sequence 7,5,3, . . .
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document.write( "You are given first three terms of an arithmetic progression 7, 5, 3.\r\n" );
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document.write( "As you see, each next term is 2 units less than the previous term.\r\n" );
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document.write( "Using this rule, continue the sequence further\r\n" );
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document.write( "    7, 5, 3, 1, -1, -3, -5, -7, -9.\r\n" );
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document.write( "Now take the sum of written terms.\r\n" );
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document.write( "Do not worry: it is easy to calculate the sum, because in the sum \r\n" );
document.write( "the negative terms will kill the positive terms.\r\n" );
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document.write( "The only term, which will survive is the term -9.\r\n" );
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document.write( "So, the sum of this sequence is -9.\r\n" );
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document.write( "At the same time, the value of -9 is the 9-th term of the progression.\r\n" );
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document.write( "Doing this way, you just answered the problem's question:\r\n" );
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document.write( "    +---------------------- A N S W E R --------------------------+\r\n" );
document.write( "    |      the value of \"n\" (the number of terms) when            |\r\n" );
document.write( "    |    the sum of progression is equal to its n-th term, is 9.  |\r\n" );
document.write( "    +-------------------------------------------------------------+\r\n" );
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