document.write( "Question 192256This question is from textbook Intermediate Algebra
\n" ); 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
\n" ); document.write( "\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)\r
\n" ); document.write( "\n" ); document.write( ".20x + .28(140-x) = 31.20\r
\n" ); document.write( "\n" ); document.write( ".20x + 39.20 - .28x = 31.20\r
\n" ); document.write( "\n" ); document.write( ".08x + 39.20 = 31.20
\n" ); document.write( "-.08x = -8.00
\n" ); document.write( "x = 1 \r
\n" ); document.write( "\n" ); document.write( "WRONG? What am I doing wrong?? Help!
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #145233 by radikrr(7)\"\" \"About 
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( "
\n" );