document.write( "Question 172863: The total value of quarters and nickels in a jar = 7.70. If the nickels were quarters and the quarters were nickels, the toal value of coins would be 4.90. Find the number of nickels. \n" ); document.write( "

Algebra.Com's Answer #127718 by Mathtut(3670) $\"\"$ $\"About$

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let n be the number of nickels and q be the number of quarters
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\n" ); document.write( ".05n+.25q=7.70
\n" ); document.write( ".05q+.25n=4.90---->.25n+.05q=4.90
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\n" ); document.write( "mulitply 1st equation by -5
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\n" ); document.write( "-.25n+-1.25q=-38.5..revised eq 1
\n" ); document.write( " .25n+ .05q=4.90
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\n" ); document.write( "-1.2q=-33.6
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\n" ); document.write( " $\"highlight%28q=28%29\"$ quarters
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\n" ); document.write( ".05n+.25(28)=7.70
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\n" ); document.write( ".05n=.70
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\n" ); document.write( " $\"highlight%28n=14%29\"$ nickels
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