document.write( "Question 827196: Hello,
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document.write( "It costs 55c for domestic mail within Australia and $2.05 to post a letter to Europe. If I spent $10.00 to post 10 letters, how many of each type did I post?
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document.write( "Could you assist by providing algebra equation?
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document.write( "Thank you,
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document.write( "Bridgit \n" );
document.write( "
Algebra.Com's Answer #498555 by rothauserc(4718)![]() ![]() You can put this solution on YOUR website! let x be the number of .55 cent letters and y be the number of $2.05 letters, then \n" ); document.write( "x +y = 10 and \n" ); document.write( ".55x +(2.05)y = 10.00 \n" ); document.write( "solve first equation for x and we get x = 10 -y, then substitute in second equation \n" ); document.write( ".55(10-y) +(2.05)y = 10.00 \n" ); document.write( "5.50 -.55y +(2.05)y = 10.00 \n" ); document.write( "(1.5)y = 4.50 \n" ); document.write( "y = 3 and x = 7 \n" ); document.write( "we have 7 letters at .55 cents each and 3 letters at $2.05 each \n" ); document.write( "let's check the answer \n" ); document.write( "7(.55) + 3(2.05) = 10.00 \n" ); document.write( "3.85 + 6.15 = 10.00 \n" ); document.write( "10.00 = 10.00 \n" ); document.write( "our answer checks :-) \n" ); document.write( " \n" ); document.write( " |