document.write( "Question 257095: I need your help with this geometric series
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document.write( " a(subscript 1)=4
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document.write( "r=3
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document.write( "S (subscript n)=484
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document.write( "n=? \n" );
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Algebra.Com's Answer #189073 by drk(1908)![]() ![]() ![]() You can put this solution on YOUR website! From the given information, the formula for the nth term is \n" ); document.write( " \n" ); document.write( "create a table to get \n" ); document.write( "T(1) = 4*3^0 = 4 \n" ); document.write( "T(2) = 4*3^1 = 12 \n" ); document.write( "T(3) = 4*3^2 = 36 \n" ); document.write( "T(4) = 4*3^3 = 108 \n" ); document.write( "T(5) = 4*3^4 = 324 \n" ); document.write( "If we add the first 5 terms we get 484. \n" ); document.write( "n = 5 \n" ); document.write( " |