document.write( "Question 956681: A man bought 42 stamps, some 13¢ and some 18¢. How many of each kind did he buy if the cost was $6.66? \n" ); document.write( "
Algebra.Com's Answer #584495 by macston(5194)![]() ![]() You can put this solution on YOUR website! X=number of $0.13; Y=number of $0.18 \n" ); document.write( "X+Y=42 \n" ); document.write( "X=42-Y \n" ); document.write( "$0.13X+$0.18Y=$6.66 Substitute for X. \n" ); document.write( "$0.13(42-Y)+$0.18Y=$6.66 \n" ); document.write( "$5.46-$0.13Y+$0.18Y=$6.66 Subtract $5.46 from each side. \n" ); document.write( "$0.05Y=$1.20 Divide each side by $0.05 \n" ); document.write( "Y=24 ANSWER1: He bought 24-18¢ stamps. \n" ); document.write( "X=42-Y=42-24=18 ANSWER 2: He bought 18-13¢ stamps. \n" ); document.write( "CHECK: \n" ); document.write( "$0.13X+$0.18Y=$6.66 \n" ); document.write( "$0.13(18)+$0.18(24)=$6.66 \n" ); document.write( "$2.34+$4.32=$6.66 \n" ); document.write( "$6.66=$6.66 \n" ); document.write( " |