document.write( "Question 1180708: Next number in this sequence:
\n" ); document.write( "240, 234, 78, 72
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Algebra.Com's Answer #810465 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
\r
\n" ); document.write( "\n" ); document.write( "\"240\", \"234\", \"78\", \"72\"\r
\n" ); document.write( "\n" ); document.write( "find differences\r
\n" ); document.write( "\n" ); document.write( "\"240\"........\"234\"........\"78\"........\"72\"
\n" ); document.write( ".........\"-6\"..........\"-156\"........\"-6\".......
\n" ); document.write( ".............\"-150\"..........\"150\"\r
\n" ); document.write( "\n" ); document.write( "...................\"300\"-> third differences are same, means nth term formula will be\r
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\n" ); document.write( "\n" ); document.write( "\"a%5Bn%5D=an%5E3%2Bbn%5E2%2Bcn%2Bd\"\r
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\n" ); document.write( "\n" ); document.write( "set up the system\r
\n" ); document.write( "\n" ); document.write( "\"240=a%2A1%5E3%2Bb%2A1%5E2%2Bc%2A1%2Bd\"
\n" ); document.write( "\"240=a%2Bb%2Bc%2Bd\".............eq.1\r
\n" ); document.write( "\n" ); document.write( "\"234=a%2A2%5E3%2Bb%2A2%5E2%2Bc%2A2%2Bd\"
\n" ); document.write( "\"234=8a%2B4b%2B2c%2Bd\".............eq.2\r
\n" ); document.write( "\n" ); document.write( "\"78=a%2A3%5E3%2Bb%2A3%5E2%2Bc%2A3%2Bd\"
\n" ); document.write( "\"78=27a%2B9b%2B3c%2Bd\".............eq.3\r
\n" ); document.write( "\n" ); document.write( "\"72=a%2A4%5E3%2Bb%2A4%5E2%2Bc%2A4%2Bd\"
\n" ); document.write( "\"72=64a%2B16b%2B4c%2Bd\".............eq.4\r
\n" ); document.write( "\n" ); document.write( "when you solve the system above, you will get\r
\n" ); document.write( "\n" ); document.write( "\"a+=+50\", \"b+=+-375\", \"c+=+769\", \"d+=+-204\"\r
\n" ); document.write( "\n" ); document.write( "and nth term formula is:\r
\n" ); document.write( "\n" ); document.write( "\"a%5Bn%5D=50n%5E3-375n%5E2%2B769n-204\"\r
\n" ); document.write( "\n" ); document.write( "the next term is \"a%5B5%5D\"=> \"n=5\"\r
\n" ); document.write( "\n" ); document.write( "\"a%5B5%5D=50%2A5%5E3-375%2A5%5E2%2B769%2A5-204\"
\n" ); document.write( "\"a%5B5%5D=516\"\r
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\n" ); document.write( "\n" ); document.write( "\"240\", \"234\", \"78\", \"72\",\"516\"\r
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