document.write( "Question 1093751: On Monday, Harold picked up six donuts and three large coffees for the office staff. He paid $6.39. On Tuesday, Melinda picked up four donuts and six large coffees for the office staff. She paid $7.50. What is the cost of one donut? What is the cost of one large coffee? \n" ); document.write( "
Algebra.Com's Answer #708358 by addingup(3677)\"\" \"About 
You can put this solution on YOUR website!
6d + 3c = 6.39 multiply all times 2 and subtract from the next equation
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\n" ); document.write( "12d + 6c = 12.78
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\n" ); document.write( "4d + 6c = 7.50
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\n" ); document.write( "8d + 0c = 5.28
\n" ); document.write( "8d = 5.28
\n" ); document.write( "d = 0.66
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\n" ); document.write( "6d + 3c = 6.39
\n" ); document.write( "6(0.66) + 3c = 6.39
\n" ); document.write( "3.96 + 3c = 6.39
\n" ); document.write( "3c = 2.43
\n" ); document.write( "c = 0.81
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\n" ); document.write( "Note: I used the first equation to solve for c, but you can use either one of the equations. Here's using the 2nd equation:
\n" ); document.write( "4d + 6c = 7.50
\n" ); document.write( "4(0.66) + 6c = 7.50
\n" ); document.write( "2.64 + 6c = 7.50
\n" ); document.write( "6c = 4.86
\n" ); document.write( "c = 0.81\r
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