document.write( "Question 1204531: Each number in a list of numbers is 3 more than the number before it. The fifth number in the list is 8. What is the first number? \n" ); document.write( "
Algebra.Com's Answer #840834 by MathLover1(20850)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "if each number in a list of numbers is \"3+\"more than the number before it, then common difference between consecutive term is \"d=3\", so we have an arithmetic sequence\r
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\n" ); document.write( "\n" ); document.write( "\"n\"-th term formula is:\r
\n" ); document.write( "\n" ); document.write( "\"a%5Bn%5D=a%5B1%5D%2Bd%28n-1%29\" where \"a%5B1%5D\" is and \"d\" is common difference \r
\n" ); document.write( "\n" ); document.write( "if the fifth number in the list is \"8\", we have \"a%5B5%5D=8\" and \"n=5\"\r
\n" ); document.write( "\n" ); document.write( "\"8=a%5B1%5D%2B3%285-1%29\" \r
\n" ); document.write( "\n" ); document.write( "\"8=a%5B1%5D%2B12\" \r
\n" ); document.write( "\n" ); document.write( "\"8-12=a%5B1%5D\" \r
\n" ); document.write( "\n" ); document.write( "\"a%5B1%5D=-4\" \r
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\n" ); document.write( "\n" ); document.write( "answer: the first number is \"-4\" \r
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\n" ); document.write( "\n" ); document.write( "and your sequence formula is:\r
\n" ); document.write( "\n" ); document.write( "\"a%5Bn%5D=-4%2B3%28n-1%29\" \r
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