document.write( "Question 192256This question is from textbook Intermediate Algebra
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document.write( ": An office has some 20 cent stamps and some 28 cent stamps. All together the office has 140 stamps for a total value of $31.20. How many of each stamp does the office have? \r
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document.write( "my try:
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document.write( "Stamps Number Value Total Value
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document.write( "20 cent x .20 .20x
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document.write( "28 cent 140 -x .28 .28(140-x)\r
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document.write( ".20x + .28(140-x) = 31.20\r
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document.write( ".20x + 39.20 - .28x = 31.20\r
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document.write( ".08x + 39.20 = 31.20
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document.write( "-.08x = -8.00
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document.write( "x = 1 \r
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document.write( "WRONG? What am I doing wrong?? Help!
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Algebra.Com's Answer #145233 by radikrr(7)![]() ![]() ![]() You can put this solution on YOUR website! An office has some 20 cent stamps and some 28 cent stamps. All together the office has 140 stamps for a total value of $31.20. How many of each stamp does the office have? \n" ); document.write( "my try: \n" ); document.write( "Stamps Number Value Total Value \n" ); document.write( "20 cent x .20 .20x \n" ); document.write( "28 cent 140 -x .28 .28(140-x) \n" ); document.write( ".20x + .28(140-x) = 31.20 \n" ); document.write( ".20x + 39.20 - .28x = 31.20 \n" ); document.write( ".08x + 39.20 = 31.20 \n" ); document.write( "-.08x = -8.00 \n" ); document.write( "x = 800/8 =100 \n" ); document.write( " |