document.write( "Question 69843: Angus invested $18,000, part at 3% and part at 5%. If the total interest at the end of the year is $660, how much did he invest at each rate? \n" ); document.write( "
Algebra.Com's Answer #49763 by Edwin McCravy(20059)\"\" \"About 
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Angus (was he a bull? J) invested $18,000, part at 3%\r\n" );
document.write( "and part at 5%.  If the total interest at the end of \r\n" );
document.write( "the year is $660, how much did he invest at each \r\n" );
document.write( "rate?\r\n" );
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document.write( "Let $x represent the first part, that is, the amount \r\n" );
document.write( "invested at 3%\r\n" );
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document.write( "Now use the formula for \"the rest\"\r\n" );
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document.write( "æThe rest of   ö    æ The  ö   æ the ö\r\n" );
document.write( "ça total amount÷  = çtotal ÷ - çfirst÷\r\n" );
document.write( "çbesides the   ÷    èamountø   è partø\r\n" );
document.write( "èfirst part    ø	\r\n" );
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document.write( "So the rest of the $18000 besides the $x\r\n" );
document.write( "is = ($18000 - $x)\r\n" );
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document.write( "This amount (the rest besides the $x) was invested\r\n" );
document.write( "at 5%. \r\n" );
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document.write( "So we have x dollars invested at 3%\r\n" );
document.write( "and (18000 - x) dollars invested at 5%\r\n" );
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document.write( "The interest on the x dollars is .03x dollars.\r\n" );
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document.write( "The interest on the (18000 - x) dollars is\r\n" );
document.write( ".05(18000 - x)\r\n" );
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document.write( "We read:\r\n" );
document.write( ">>...the total interest at the end of the year \r\n" );
document.write( "is $660...<<\r\n" );
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document.write( "|Interest |     |Interest|\r\n" );
document.write( "|   on    |     |   on   |\r\n" );
document.write( "|  the    |  +  |  the   |  =  $660 \r\n" );
document.write( "|x dollars|     |18000-x |\r\n" );
document.write( "                |dollars |\r\n" );
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document.write( "     .03x    +  .05(18000-x) = 660\r\n" );
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document.write( "Can you solve that? If not post again asking how.\r\n" );
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document.write( "You get x = $12000, which is the amount invested\r\n" );
document.write( "at 3%.\r\n" );
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document.write( "To get the rest, which was invested at 5%, subtract\r\n" );
document.write( "that $12000 from the total, $18000, and get $6000, \r\n" );
document.write( "the amount invested at 5%.\r\n" );
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document.write( "Edwin
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