document.write( "Question 667740: A man has $2000 invested at 7% and $5000 at 4% simple interest. What additional sum must he invest at 6% to give him an overall return of 5%?
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Algebra.Com's Answer #415149 by mananth(16946)\"\" \"About 
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Investment I 7.00% 2000
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\n" ); document.write( "Investment III 6.00% x
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\n" ); document.write( "Total 5.00%
\n" ); document.write( "The sum of individual interest earned = 5.00% of Total investment
\n" ); document.write( "Total Interest
\n" ); document.write( "7.00%*2000+4.00%*5000+6.00%x=5.00%(2000+5000+x)
\n" ); document.write( "140+ 200 + 6.00% x = 350 + 5.00% x
\n" ); document.write( "6.00% x- 5.00% x= 350 -140 -200
\n" ); document.write( "1.00% x= 10
\n" ); document.write( " x= 1000
\n" ); document.write( "He has to invest $ 1000
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\n" ); document.write( "CHECK
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\n" ); document.write( "140 200 60 = 400
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\n" ); document.write( "Total = 8000
\n" ); document.write( "5.00% on 8000 = 400
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