document.write( "Question 727805: How many terms of the progression 3, 6, 9, 12,....
\n" ); document.write( "must be taken at the least to have a sum not less than 2000? \n" ); document.write( "

Algebra.Com's Answer #445214 by josgarithmetic(39618) $\"\"$ $\"About$

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Finding or evaluating finite arithmetic series is $\"%28n%2F2%29%282a%5B1%5D%2B%28n-1%29d%29\"$ , where n is the index of the final term, $\"a%5B1%5D\"$ is the first term, and d is the common difference between terms.\r
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\n" ); document.write( "\n" ); document.write( "Your example would use the expression for the sum as $\"%28n%2F2%29%282%2A3%2B%28n-1%29%2A3%29\"$ , and because you want this value to be \"not less than 2000\", you want the inequality statement,
\n" ); document.write( " $\"highlight%28%28n%2F2%29%282%2A3%2B%28n-1%29%2A3%29%3E=2000%29\"$ . Solve for n. \n" ); document.write( "

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