document.write( "Question 214746: Galina spent $3.60 for stamps to mail packages. Some were 30¢ stamps and the rest were 20¢ stamps. The number of 20¢ stamps was 2 less than the number of 30¢ stamps. How many stamps of each kind did Galina buy? \n" ); document.write( "

Algebra.Com's Answer #162203 by stanbon(75887) $\"\"$ $\"About$

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Galina spent $3.60 for stamps to mail packages. Some were 30¢ stamps and the rest were 20¢ stamps. The number of 20¢ stamps was 2 less than the number of 30¢ stamps. How many stamps of each kind did Galina buy?
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\n" ); document.write( "Equations:
\n" ); document.write( "Quantity Eq.: w = r -2
\n" ); document.write( "Value Eq.::::20w + 30r = 360 cents
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\n" ); document.write( "Rearrange the Equations:
\n" ); document.write( "2w - 2r = -4
\n" ); document.write( "2w + 3r = 36
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\n" ); document.write( "Subtract the 1st from the 2nd:
\n" ); document.write( "5r = 40
\n" ); document.write( "r = 8 (# of thirty-cent stamps)
\n" ); document.write( "w = r-2, so w = 6 (# of twenty-cent stamps)
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\n" ); document.write( "Checking
\n" ); document.write( "8*30+6*20 = 240 + 120 = 360 cents
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "

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