document.write( "Question 856060: A book shop owner orders some hard-back and some soft-back versions of a book costing the shop owner $20 and $12 respectively. The total order was for 300 books.
\n" ); document.write( "When the order arrives there were only 200 books. The shopkeeper wishes to query the order but cannot find his copy of the original order. However, his records do tell him that it was going to cost him $5080. How many of each type of the book was his original order for? \n" ); document.write( "

Algebra.Com's Answer #515715 by mananth(16946) $\"\"$ $\"About$

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x= cost of hardbound
\n" ); document.write( "y= cost of softback
\n" ); document.write( "
\n" ); document.write( "1 x + 1 y = 300 .............1
\n" ); document.write( "Total value
\n" ); document.write( "20 x + 12 y = 5080 .............2
\n" ); document.write( "Eliminate y
\n" ); document.write( "multiply (1)by -12
\n" ); document.write( "Multiply (2) by 1
\n" ); document.write( "-12 x -12 y = -3600
\n" ); document.write( "20 x + 12 y = 5080
\n" ); document.write( "Add the two equations
\n" ); document.write( "8 x = 1480
\n" ); document.write( "/ 8
\n" ); document.write( "x = 185
\n" ); document.write( "plug value of x in (1)
\n" ); document.write( "1 x + 1 y = 300
\n" ); document.write( "185 + y = 300
\n" ); document.write( " y = 300 -185
\n" ); document.write( " y = 115
\n" ); document.write( " y = 115
\n" ); document.write( "x= 185 cost of hardbound
\n" ); document.write( "y= 115 cost of softback
\n" ); document.write( "m.ananth@hotmail.ca
\n" ); document.write( " \n" ); document.write( "

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