document.write( "Question 127310This question is from textbook Introductory and Intermediate Algebra
\n" ); document.write( ": A man has twenty coins consisting of dimes and quarters. If the dimes were quarters and the quarters were dimes, he would have ninety cents more than he has now. How many dimes and quarters does he have? \n" ); document.write( "

Algebra.Com's Answer #93285 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"d\"$ = actual number of dimes
\n" ); document.write( "Let $\"q\"$ = actual number of quatrers
\n" ); document.write( " $\"d+%2B+q+=+20\"$
\n" ); document.write( "The amount of money he actually has is $\"10d+%2B+25q\"$
\n" ); document.write( "The problem says $\"25d+%2B+10q+=+10d+%2B+25q+%2B+90\"$
\n" ); document.write( " $\"25d+-+10d+-+25q+%2B+10q+=+90\"$
\n" ); document.write( " $\"15d+-+15q+=+90\"$
\n" ); document.write( " $\"15%28d+-+q%29+=+90\"$
\n" ); document.write( " $\"d+-+q+=+6\"$
\n" ); document.write( " $\"d+=+q+%2B+6\"$
\n" ); document.write( "and from above
\n" ); document.write( " $\"d+%2B+q+=+20\"$
\n" ); document.write( " $\"q+%2B+6+%2B+q+=+20\"$
\n" ); document.write( " $\"2q+=+14\"$
\n" ); document.write( " $\"q+=+7\"$
\n" ); document.write( " $\"d+=+q+%2B+6\"$
\n" ); document.write( " $\"d+=+7+%2B+6\"$
\n" ); document.write( " $\"d+=+13\"$
\n" ); document.write( "He has 13 dimes and 7 quarters
\n" ); document.write( "check:
\n" ); document.write( " $\"15%28d+-+q%29+=+90\"$
\n" ); document.write( " $\"15%2813+-+7%29+=+90\"$
\n" ); document.write( " $\"15%2A6+=+90\"$
\n" ); document.write( " $\"90+=+90\"$
\n" ); document.write( "OK \n" ); document.write( "

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