document.write( "Question 380481: Joe has a collection of nickels and dimes that is worth $6.00. If the number of dimes was doubled and the number of nickels was increased by 6, the value of the coins would be $9.90. How many dimes does he have? \n" ); document.write( "
Algebra.Com's Answer #270050 by stanbon(75887)\"\" \"About 
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Joe has a collection of nickels and dimes that is worth $6.00. If the number of dimes was doubled and the number of nickels was increased by 6, the value of the coins would be $9.90. How many dimes does he have?
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\n" ); document.write( "Value Eq: 5n + 10d = 600 cents
\n" ); document.write( "Value Eq: 5(n+6)+10(2d) = 990 cents
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\n" ); document.write( "Rearrange and modify to get:
\n" ); document.write( "5n+ 20d = 990-30
\n" ); document.write( "5n+ 10d = 600
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\n" ); document.write( "Subtract bottom from top and solve for \"d\":
\n" ); document.write( "10d = 360
\n" ); document.write( "d = 36 (# of dimes)
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\n" ); document.write( "Substitute and solve for \"n\":
\n" ); document.write( "5n+10*36 = 600
\n" ); document.write( "5n+360 = 600
\n" ); document.write( "5n = 240
\n" ); document.write( "n = 48 (# of nickels)
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\n" ); document.write( "Cheers,
\n" ); document.write( "stan H. \n" ); document.write( "
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