document.write( "Question 145296: Allen bought 56 stamps at the post office in 37 cent and 20 cent denominations. If the total cost of the stamps was $18, how many of each denomination did Allen buy? \n" ); document.write( "
Algebra.Com's Answer #105966 by ankor@dixie-net.com(22740)\"\" \"About 
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Allen bought 56 stamps at the post office in 37 cent and 20 cent denominations. If the total cost of the stamps was $18, how many of each denomination did Allen buy?
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\n" ); document.write( "Let x = no. of 37 cent stamps
\n" ); document.write( "Let y = no. of 20 cent stamps
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\n" ); document.write( "Total no. of stamps given as 56, therefore:
\n" ); document.write( "x + y = 56
\n" ); document.write( "or
\n" ); document.write( "y = (56-x)
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\n" ); document.write( "Total cost given as $18, therefore:
\n" ); document.write( ".37x+ 2.0y = 18
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\n" ); document.write( "Substitute (56-x) for y and find x:
\n" ); document.write( ".37x + .20(56-x) = 18
\n" ); document.write( ":
\n" ); document.write( ".37x + 11.2 - .20x = 18
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\n" ); document.write( ".37x - .20x = 18 - 11.2
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\n" ); document.write( ".17x = 6.8
\n" ); document.write( "x = \"6.8%2F.17\"
\n" ); document.write( "x = 40 ea 37 cent stamps
\n" ); document.write( "and
\n" ); document.write( "56 - 40 = 16 ea 20 cent stamps
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\n" ); document.write( "Check solution:
\n" ); document.write( ".37(40) + .20(16) = 18 \n" ); document.write( "
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