document.write( "Question 899568: Maria bought 80 stamps at the post office in 33¢ and 25¢ denominations. If she paid $24 for the stamps, how many of each denomination did she buy?\r
\n" ); document.write( "\n" ); document.write( "Here is what I tried:\r
\n" ); document.write( "\n" ); document.write( "x=33¢ denomination
\n" ); document.write( "y=25¢ denomination\r
\n" ); document.write( "\n" ); document.write( "x+y=80
\n" ); document.write( "x=-y+80\r
\n" ); document.write( "\n" ); document.write( "33(x)+25(y)=24
\n" ); document.write( "33(-y+80)+25y=2400
\n" ); document.write( "-33y+(-2640)+25y=2400
\n" ); document.write( "Added 2640 to both sides
\n" ); document.write( "8y=50.4
\n" ); document.write( "Divide both sides by 8
\n" ); document.write( "y=6.30\r
\n" ); document.write( "\n" ); document.write( "x=-6.30+80
\n" ); document.write( "x=50.4\r
\n" ); document.write( "\n" ); document.write( "which Ido not think is right but I can not figure what I am doing wrong :(
\n" ); document.write( " \n" ); document.write( "

Algebra.Com's Answer #545497 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi
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document.write( "x+y=80
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document.write( " x=-y+80 
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document.write( " 33(x)+25(y)=24
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document.write( " 33(-y+80)+25y=2400  Nice Work...careful to the finish line 
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document.write( " -33y+(2640)+25y=2400  
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document.write( "   -8y = -240
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document.write( "     y = 30, number of 25cent stamps.  50 33cent stamps 
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document.write( "CHECKING our answer***
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document.write( " 30*25 + 50*33 = 2400 \n" );
document.write( "

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