document.write( "Question 277598: I was hoping someone could help me with this Question and show me how you put it in an equation. I'm fine until it gets put in a word problem? I'd like to practice to see what I'm doing wrong.
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\n" ); document.write( "\n" ); document.write( "A person invests $36,000, partly at 5%, partly at 6%, and the remainder at 6.5%. The total annual interest is $2,190. Three times the amount invested at 6% equals the amount invested at 5% and 6.5% combined. How much is invested at each rate?
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Algebra.Com's Answer #202225 by ankor@dixie-net.com(22740)\"\" \"About 
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A person invests $36,000, partly at 5%, partly at 6%, and the remainder at 6.5%.
\n" ); document.write( " The total annual interest is $2,190.
\n" ); document.write( "Three times the amount invested at 6% equals the amount invested at 5% and 6.5% combined.
\n" ); document.write( "How much is invested at each rate?
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\n" ); document.write( "Let a = amt at 5%
\n" ); document.write( "Let b = amt at 6%
\n" ); document.write( "let c - amt at 6.5%
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\n" ); document.write( "Write an equation for each statement:
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\n" ); document.write( "\"A person invests $36,000,\"
\n" ); document.write( "a + b + c = 36000
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\n" ); document.write( "\"The total annual interest is $2,190.\"
\n" ); document.write( ".05a + .06b + .065c = 2190
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\n" ); document.write( "\"Three times the amount invested at 6% equals the amount invested at 5% and 6.5% combined.\"
\n" ); document.write( "3b = a + c
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\n" ); document.write( "How much is invested at each rate?
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\n" ); document.write( "We can replace a + c in the 1st equation with 3b
\n" ); document.write( "3b + b = 36000
\n" ); document.write( "4b = 36000
\n" ); document.write( "b = \"36000%2F4\"
\n" ); document.write( "b = $9000 invested at 6%
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\n" ); document.write( "We know that:
\n" ); document.write( "a + c = 3(9000)
\n" ); document.write( "a + c = 27000
\n" ); document.write( "therefore:
\n" ); document.write( "a = (27000-c)
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\n" ); document.write( "In the 2nd (interest) equation replace a with (27000-c), replace b with 9000, find c
\n" ); document.write( ".05(27000-c) + .06(9000) + .065c = 2190
\n" ); document.write( "1350 - .05c + 540 + .065c = 2190
\n" ); document.write( ".05c + .065c = 2190 - 1350 - 540
\n" ); document.write( ".015c = 300
\n" ); document.write( "c = \"300%2F.015\"
\n" ); document.write( "c = $20000 invest at 6.5%
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\n" ); document.write( "I'll let you find the amt invested at 5% (a)
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\n" ); document.write( "Check the total interest then\r
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