document.write( "Question 120557: Sally has $21.40 in dimes and quaters, for a total of 100 coins.How many of each kind of coins does Sally have?\r
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Algebra.Com's Answer #88410 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
d = no. of dimes;
\n" ); document.write( "q = no. of quarters
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\n" ); document.write( "Translate each statement into a simple equation:
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\n" ); document.write( "\"Sally has $21.40 in dimes and quarters,\"
\n" ); document.write( ".10d + .25q = 21.40
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\n" ); document.write( "for a total of 100 coins.\"
\n" ); document.write( " d + q = 100
\n" ); document.write( " d = (100-q); in this form we can use it for substitution
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\n" ); document.write( "How many of each kind of coins does Sally have?
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\n" ); document.write( "Substitute (100-q) for d in the $value equation and solve for q
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\n" ); document.write( ".10(100-q) + .25q = 21.40
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\n" ); document.write( "10 - .10q + .25q = 21.40
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\n" ); document.write( ".15q = 21.40 - 10
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\n" ); document.write( ".15q = 11.40
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\n" ); document.write( "q = 11.40/.15
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\n" ); document.write( "q = 76 quarters
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\n" ); document.write( "Remember we said d = 100 - q
\n" ); document.write( "d = 100 - 76
\n" ); document.write( "d = 24 dimes
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\n" ); document.write( "Check our solutions in the value equation:
\n" ); document.write( ".10(24) + .25(76) =
\n" ); document.write( "2.4 + 19 = 21.40 as expected
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\n" ); document.write( "Did I make this understandable to you? Let me know.
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