document.write( "Question 322815: Your piggy bank has a total of 40 coins in it. Some are dimes and some are nickles. If you have a total of $3.50, how many dimes do you have? \n" ); document.write( "

Algebra.Com's Answer #231123 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"d\"$ = number of dimes
\n" ); document.write( "Let $\"n\"$ = number of nickels
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"d+%2B+n+=+40\"$
\n" ); document.write( "(2) $\"10d+%2B+5n+=+350\"$ (in cents)
\n" ); document.write( "Multiply both sides of (1) by $\"5\"$ and
\n" ); document.write( "subtract (1) from (2)
\n" ); document.write( "(2) $\"10d+%2B+5n+=+350\"$
\n" ); document.write( "(1) $\"-5d+-+5n+=+-200\"$
\n" ); document.write( " $\"5d+=+150\"$
\n" ); document.write( " $\"d+=+30\"$
\n" ); document.write( "and
\n" ); document.write( " $\"30+%2B+n+=+40\"$
\n" ); document.write( " $\"n+=+10\"$
\n" ); document.write( "There are 30 dimes and 10 nickels \n" ); document.write( "

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