document.write( "Question 172794: Find the sum \r
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Algebra.Com's Answer #127636 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Note: there are \"305-150%2B1=156\" terms that need to be added.\r
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\n" ); document.write( "\n" ); document.write( "\"sum%284i-5%2Ci=150%2C305%29\" Start with the given summation\r
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\n" ); document.write( "\n" ); document.write( "\"sum%284i%2Ci=150%2C305%29%2Bsum%28-5%2Ci=150%2C305%29\" Break up the summation\r
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\n" ); document.write( "\n" ); document.write( "\"sum%284i%2Ci=150%2C305%29%2B%28-5%29%2A%28156%29\" Since the 2nd term has no variables, we can simply multiply the inner value -5 by the number of terms 156\r
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\n" ); document.write( "\n" ); document.write( "\"sum%284i%2Ci=150%2C305%29-780\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"4%2Asum%28i%2Ci=150%2C305%29-780\" Pull out the coefficient 4\r
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\n" ); document.write( "\n" ); document.write( "Now this is where the formula \"sum%28i%2Ci=1%2Cn%29=%28n%28n%2B1%29%29%2F2\" comes in. There's one small problem though: the terms NEED to start at 1. So what this means is that we have to break \"sum%28i%2Ci=150%2C305%29\" into \r
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\n" ); document.write( "\n" ); document.write( "\"sum%28i%2Ci=150%2C305%29=sum%28i%2Ci=1%2C305%29-sum%28i%2Ci=1%2C149%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"sum%28i%2Ci=150%2C305%29=%28305%28305%2B1%29%29%2F2-%28149%28149%2B1%29%29%2F2\" Now use the formula \"sum%28i%2Ci=1%2Cn%29=%28n%28n%2B1%29%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"sum%28i%2Ci=150%2C305%29=%28305%28306%29%29%2F2-%28149%28150%29%29%2F2\" Add\r
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\n" ); document.write( "\n" ); document.write( "\"sum%28i%2Ci=150%2C305%29=305%28153%29-149%2875%29\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "\"sum%28i%2Ci=150%2C305%29=46665-11175\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"sum%28i%2Ci=150%2C305%29=35490\" Subtract\r
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\n" ); document.write( "\n" ); document.write( "So the expression \r
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\n" ); document.write( "\n" ); document.write( "\"4%2Asum%28i%2Ci=150%2C305%29-780\" \r
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\n" ); document.write( "\n" ); document.write( "then becomes\r
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\n" ); document.write( "\n" ); document.write( "\"4%2A%2835490%29-780\" \r
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\n" ); document.write( "\n" ); document.write( "\"141960-780\" Multiply\r
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\n" ); document.write( "\n" ); document.write( "\"141180\" Subtract\r
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\n" ); document.write( "\n" ); document.write( "So this means that \"sum%284i-5%2Ci=150%2C305%29=141180\"
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