document.write( "Question 1096643: Carlos invested part of $2000 in a 10% certificate account and the rest in a 6% passbook account. The total annual interest from both accounts is $180. How much did he invest at 6%? \n" ); document.write( "
Algebra.Com's Answer #753226 by VFBundy(438)\"\" \"About 
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10% certificate:
\n" ); document.write( "Principal = p
\n" ); document.write( "Rate = 0.10
\n" ); document.write( "Interest = 0.10p
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\n" ); document.write( "6% passbook:
\n" ); document.write( "Principal = 2000 - p
\n" ); document.write( "Rate = 0.06
\n" ); document.write( "Interest = 0.06(2000 - p) = 120 - 0.06p
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\n" ); document.write( "Total interest:
\n" ); document.write( "
\n" ); document.write( "0.10p + (120 - 0.06p) = 180
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\n" ); document.write( "Simplify:
\n" ); document.write( "
\n" ); document.write( "0.04p = 60
\n" ); document.write( "
\n" ); document.write( "Solve for p:
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\n" ); document.write( "p = 1500
\n" ); document.write( "
\n" ); document.write( "From earlier:
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\n" ); document.write( "6% passbook:
\n" ); document.write( "Principal = 2000 - p = 2000 - 1500 = 500
\n" ); document.write( "
\n" ); document.write( "Carlos invested $500 at 6%. \n" ); document.write( "
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