document.write( "Question 761754: given the sequence: 5,8,11,......,101 find the number of terms \n" ); document.write( "
Algebra.Com's Answer #464206 by Edwin McCravy(20056)\"\" \"About 
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document.write( "given the sequence: 5,8,11,......,101 find the number of terms\r\n" );
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document.write( "a1 = first term = 5\r\n" );
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document.write( "d = a2 - a1 = 8 - 5 = 3\r\n" );
document.write( "d = a3 - a2 = 11 - 8 = 3\r\n" );
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document.write( "Since those are the same, the sequence is arithmetic.\r\n" );
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document.write( "an = a1 + (n-1)d\r\n" );
document.write( "101 = 5 + (n - 1)(3)\r\n" );
document.write( "101 = 5 + 3(n - 1)\r\n" );
document.write( "101 = 5 + 3n - 3\r\n" );
document.write( "101 = 2 + 3n\r\n" );
document.write( " 99 = 3n\r\n" );
document.write( " 33 = n\r\n" );
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document.write( "Checking:\r\n" );
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document.write( "  5,8,11,14,17,20,23,26,29,32,35,\r\n" );
document.write( "38,41,44,47,50,53,56,59,62,65,68,\r\n" );
document.write( "71,74,77,80,83,86,89,92,95,98,101\r\n" );
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document.write( "Count them.  There are 33 of them.\r\n" );
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document.write( "Edwin
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