document.write( "Question 970722: Kate has 21 coins (nickels and dimes) in her purse. How many nickels and dimes does she have if she has $1.50?\r
\n" ); document.write( "\n" ); document.write( "3 nickels and 18 dimes\r
\n" ); document.write( "\n" ); document.write( "5 nickels and 16 dimes\r
\n" ); document.write( "\n" ); document.write( "12 nickels and 9 dimes\r
\n" ); document.write( "\n" ); document.write( "15 nickels and 6 dimes \n" ); document.write( "
Algebra.Com's Answer #593348 by macston(5194)\"\" \"About 
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\n" ); document.write( "N=number of nickels; D=number of dimes
\n" ); document.write( "N+D=21
\n" ); document.write( "D=21-N Use this to substitute for D
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\n" ); document.write( "$0.05N+$0.10D=$1.50 Substitute for D. (This converts number of coins to value)
\n" ); document.write( "$0.05N+$0.10(21-N)=$1.50
\n" ); document.write( "$0.05N+$2.10-$0.10N=$1.50 Subtract $2.10 from each side.
\n" ); document.write( "-$0.05N=-$0.60 Divide each side by -$0.05
\n" ); document.write( "N=12 ANSWER 1: She has 12 nickels.
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\n" ); document.write( "D=21-N=21-12=9 ANSWER 2: She has 9 dimes
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\n" ); document.write( "CHECK:
\n" ); document.write( "$0.05N+$0.10D=$1.50
\n" ); document.write( "$0.05(12)+$0.10(9)=$1.50
\n" ); document.write( "$0.60+$0.90=$1.50
\n" ); document.write( "$1.50=$1.50\r
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