document.write( "Question 614212: Joe has a collection of nickels and dimes that is worth $6.20. If the number of dimes was doubled and the number of nickels was decreased by 7, the value of the coins would be $10.35. How many nickels and dimes does he have? \n" ); document.write( "
Algebra.Com's Answer #386452 by lwsshak3(11628)\"\" \"About 
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Joe has a collection of nickels and dimes that is worth $6.20. If the number of dimes was doubled and the number of nickels was decreased by 7, the value of the coins would be $10.35. How many nickels and dimes does he have?
\n" ); document.write( "**
\n" ); document.write( "let x= number of dimes
\n" ); document.write( "let y=number of nickels
\n" ); document.write( "===
\n" ); document.write( ".10x+.05y=6.20
\n" ); document.write( ".10(2x)+.05(y-7)=10.35
\n" ); document.write( "===
\n" ); document.write( ".10x+.05y=6.20
\n" ); document.write( ".20x+.05y-.35=10.35
\n" ); document.write( "===
\n" ); document.write( "10x+5y=620
\n" ); document.write( "20x+5y=1070
\n" ); document.write( "subtract
\n" ); document.write( "10x=450
\n" ); document.write( "x=45
\n" ); document.write( "5y=620-10x=620-450=170
\n" ); document.write( "y=170/5=34
\n" ); document.write( "ans:
\n" ); document.write( "number of dimes=45
\n" ); document.write( "number of nickels=34
\n" ); document.write( " \n" ); document.write( "
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