document.write( "Question 885867: A couple invested part of P2,100,000 at 4% and the remainder at 7%. Their annual income from these two investments was equivalent to a return at 6% on the entire sum invested. how much money was invested at each rate?
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Algebra.Com's Answer #535559 by mananth(16946)\"\" \"About 
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Part I 4.00% per annum ------------- Amount invested =x
\n" ); document.write( "Part II 7.00% per annum ------------ Amount invested = y
\n" ); document.write( " 2100000
\n" ); document.write( "6% of 21,000,000 = 126,000
\n" ); document.write( "Interest----- 126000.00
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\n" ); document.write( "Part I 4.00% per annum ---x
\n" ); document.write( "Part II 7.00% per annum ---y
\n" ); document.write( "Total investment
\n" ); document.write( "x + 1 y= 2100000 -------------1
\n" ); document.write( "Interest on both investments
\n" ); document.write( "4.00% x + 7.00% y= 126000
\n" ); document.write( "Multiply by 100
\n" ); document.write( "4 x + 7 y= 12600000.00 --------2
\n" ); document.write( "Multiply (1) by -4
\n" ); document.write( "we get
\n" ); document.write( "-4 x -4 y= -8400000.00
\n" ); document.write( "Add this to (2)
\n" ); document.write( "0 x 3 y= 4200000
\n" ); document.write( "divide by 3
\n" ); document.write( " y = 1400000
\n" ); document.write( "Part I 4.00% $ 700000
\n" ); document.write( "Part II 7.00% $ 1400000
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\n" ); document.write( "CHECK
\n" ); document.write( "700000 --------- 4.00% ------- 28000.00
\n" ); document.write( "1400000 ------------- 7.00% ------- 98000.00
\n" ); document.write( "Total -------------------- 126000.00
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\n" ); document.write( "m.ananth@hotmail.ca
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