document.write( "Question 865364: Susan inherited $12,000 and invested some of it in an account earning 5% simple interest and put the rest in an account earning 8% simple interest. If she earned a total of $810 in interest after 1 year, how much did she invest in each account? \n" ); document.write( "
Algebra.Com's Answer #521646 by mananth(16946)\"\" \"About 
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Part I 5.00% per annum ------------- Amount invested =x
\n" ); document.write( "Part II 8.00% per annum ------------ Amount invested = y
\n" ); document.write( " 12000
\n" ); document.write( "Interest----- 810.00
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\n" ); document.write( "Part I 5.00% per annum ---x
\n" ); document.write( "Part II 8.00% per annum ---y
\n" ); document.write( "Total investment
\n" ); document.write( "x + 1 y= 12000 -------------1
\n" ); document.write( "Interest on both investments
\n" ); document.write( "5.00% x + 8.00% y= 810
\n" ); document.write( "Multiply by 100
\n" ); document.write( "5 x + 8 y= 81000.00 --------2
\n" ); document.write( "Multiply (1) by -5
\n" ); document.write( "we get
\n" ); document.write( "-5 x -5 y= -60000.00
\n" ); document.write( "Add this to (2)
\n" ); document.write( "0 x 3 y= 21000
\n" ); document.write( "divide by 3
\n" ); document.write( " y = 7000
\n" ); document.write( "Part I 5.00% $ 5000
\n" ); document.write( "Part II 8.00% $ 7000
\n" ); document.write( "
\n" ); document.write( "CHECK
\n" ); document.write( "5000 --------- 5.00% ------- 250.00
\n" ); document.write( "7000 ------------- 8.00% ------- 560.00
\n" ); document.write( "Total -------------------- 810.00
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\n" ); document.write( "m.ananth@hotmail.ca
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