document.write( "Question 163817: An investor will invest a total of $15000 in two accounts, one paying 4% annual simple interest and the other 3%. If he wants to earn $550 annual interest, how much should he invest at each rate? \n" ); document.write( "

Algebra.Com's Answer #120681 by SAT Math Tutor(36) $\"\"$ $\"About$

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You need to set up 2 linear equations with variables x and y where x represents the amount invested in account 1 and y represents the amount represented in account 2.\r
\n" ); document.write( "\n" ); document.write( "x + y = 15000\r
\n" ); document.write( "\n" ); document.write( "x*.04 + y*.03 = 550\r
\n" ); document.write( "\n" ); document.write( "Solve the first equation for x:\r
\n" ); document.write( "\n" ); document.write( "x = 15000 - y\r
\n" ); document.write( "\n" ); document.write( "Plug this into the second equation:\r
\n" ); document.write( "\n" ); document.write( "(15000 - y)*.04 + y*.03 = 550\r
\n" ); document.write( "\n" ); document.write( "Then, solve:\r
\n" ); document.write( "\n" ); document.write( "600 - .04*y + y*.03 = 550
\n" ); document.write( "600 - .01*y = 550
\n" ); document.write( "-.01*y = -50
\n" ); document.write( "y = 5000\r
\n" ); document.write( "\n" ); document.write( "So, going back to what we have for x:\r
\n" ); document.write( "\n" ); document.write( "x = 15000 - 5000 = 10000\r
\n" ); document.write( "\n" ); document.write( "So y = 5000, x = 10000 \n" ); document.write( "

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