document.write( "Question 1154199: 3, -6, 12, 4, 20, ? which number comes next \n" ); document.write( "

Algebra.Com's Answer #776588 by Edwin McCravy(20056) $\"\"$ $\"About$

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It is with great sorrow that Ikleyn does not know that numerical reasoning\r\n" );
document.write( "tests for employment nearly always contain many sequences just like this one.\r\n" );
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document.write( "3, -6, 12, 4, 20, ? which number comes next\r\n" );
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document.write( "We look at the sequence of differences:\r\n" );
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document.write( "3  -6  12  4  20\r\n" );
document.write( " -9  18  -8 16\r\n" );
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document.write( "The sequence of differences looks like it's going like this\r\n" );
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document.write( " -9  18  -8 16 -7 14 -6 12 -5 10 -4 8 ... \r\n" );
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document.write( "where the odd terms are going  -9, -8, -7, -6, -5, -4,... \r\n" );
document.write( "and the even terms are going 18, 16, 14, 12, 10, 8,... \r\n" );
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document.write( "So to get the next term of \r\n" );
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document.write( "3, -6, 12, 4, 20,\r\n" );
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document.write( "We stick a -7 on the sequence of differences:\r\n" );
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document.write( "3  -6  12  4  20\r\n" );
document.write( " -9  18  -8 16  -7\r\n" );
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document.write( "Then we add the 20 and the -7 to get the next term:\r\n" );
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document.write( "3  -6  12  4  20  13\r\n" );
document.write( " -9  18  -8 16  -7\r\n" );
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document.write( "which is 13.\r\n" );
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document.write( "Edwin
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