document.write( "Question 911078: Phoebe wishes to invest $20,000 part at 7% interest and the rest at 6.5% if her total income from the two investment for one year is $1370 how much should she invest at each rate? \n" ); document.write( "
Algebra.Com's Answer #552853 by mananth(16946)\"\" \"About 
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Part I 7.00% per annum ------------- Amount invested =x
\n" ); document.write( "Part II 6.50% per annum ------------ Amount invested = y
\n" ); document.write( " 20000
\n" ); document.write( "Interest----- 1370.00
\n" ); document.write( "
\n" ); document.write( "Part I 7.00% per annum ---x
\n" ); document.write( "Part II 6.50% per annum ---y
\n" ); document.write( "Total investment
\n" ); document.write( "x + 1 y= 20000 -------------1
\n" ); document.write( "Interest on both investments
\n" ); document.write( "7.00% x + 6.50% y= 1370
\n" ); document.write( "Multiply by 100
\n" ); document.write( "7 x + 6.5 y= 137000.00 --------2
\n" ); document.write( "Multiply (1) by -7
\n" ); document.write( "we get
\n" ); document.write( "-7 x -7 y= -140000.00
\n" ); document.write( "Add this to (2)
\n" ); document.write( "0 x -0.5 y= -3000
\n" ); document.write( "divide by -0.5
\n" ); document.write( " y = 6000
\n" ); document.write( "Part I 7.00% $ 14000
\n" ); document.write( "Part II 6.50% $ 6000
\n" ); document.write( "
\n" ); document.write( "CHECK
\n" ); document.write( "14000 --------- 7.00% ------- 980.00
\n" ); document.write( "6000 ------------- 6.50% ------- 390.00
\n" ); document.write( "Total -------------------- 1370.00
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\n" ); document.write( "m.ananth@hotmail.ca
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