document.write( "Question 619934: on monday harold picked five donuts and six large coffees he paid $8.65
\n" ); document.write( "on tuesday he picked three donuts and five coffees he paid $6.38. what's the cost of one donut and the cost of one large coffee \n" ); document.write( "

Algebra.Com's Answer #389863 by stanbon(75887) $\"\"$ $\"About$

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on monday harold picked five donuts and six large coffees he paid $8.65
\n" ); document.write( "on tuesday he picked three donuts and five coffees he paid $6.38. what's the cost of one donut and the cost of one large coffee
\n" ); document.write( "------
\n" ); document.write( "Equation:
\n" ); document.write( "5d + 6c = 865 cents
\n" ); document.write( "3d + 5c = 638 cents
\n" ); document.write( "------------------------
\n" ); document.write( "Multiply thru 1st by 3:
\n" ); document.write( "Multiply thru 2nd by 5:
\n" ); document.write( "15d + 18c = 3*865
\n" ); document.write( "15d + 25c = 5*638
\n" ); document.write( "---
\n" ); document.write( "Subtract and solve for \"c\":
\n" ); document.write( "7c = 595
\n" ); document.write( "c = 75 cents (cost on one large coffee)
\n" ); document.write( "----
\n" ); document.write( "solve for \"d\":
\n" ); document.write( "3d + 5c = 638 cents
\n" ); document.write( "3d + 5*75 = 638
\n" ); document.write( "3d = 263
\n" ); document.write( "d = 87 2/3 cents (cost of one donut)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
\n" ); document.write( "=============== \n" ); document.write( "

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