document.write( "Question 574161: a collection of dimes and quarters is worth $16.20. there are 81 coins in all. how many dimes and how many quarters? \n" ); document.write( "

Algebra.Com's Answer #368983 by Maths68(1474) $\"\"$ $\"About$

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\n" ); document.write( "Let
\n" ); document.write( "Quarters=x
\n" ); document.write( "Dimes=81-x
\n" ); document.write( "Total Coins=81
\n" ); document.write( "Value of a Quarter = $0.25
\n" ); document.write( "Value of a Dime = $0.10
\n" ); document.write( "Total value of all coins = $16.20\r
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\n" ); document.write( "\n" ); document.write( "(Value of a Quarter)(Quarters)+(Value of a Dimes)(Dimes)= Total value of all coins\r
\n" ); document.write( "\n" ); document.write( "(0.25)(x)+(0.10)(81-x)=16.20
\n" ); document.write( "0.25x+8.1-0.10x=16.20
\n" ); document.write( "0.25x-0.10x=16.20-8.10
\n" ); document.write( "0.15x=8.1
\n" ); document.write( "0.15x/0.15=8.1/0.15
\n" ); document.write( "x=54\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Quarters=x=54
\n" ); document.write( "Dimes=81-x=81-54=27\r
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\n" ); document.write( "\n" ); document.write( "Check
\n" ); document.write( "=====
\n" ); document.write( "Total Quarters*value of a Quarter+Total Dimes*value of a Dime = Total Amount
\n" ); document.write( "54*0.25+27*0.1=16.20
\n" ); document.write( "13.5+2.7=16.20
\n" ); document.write( "16.20=16.20\r
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