document.write( "Question 409767: I have a lemonade stand and charged $1.00 per cup and sold 48 cups. When I raised the price to $2.00 per cup I only sold 27 cups. I need to write an equation for the number of cups I sold as a function of the price I charged. \"C\" would be for the number of cups and \"P\" would denote the price I charged. I have to assume the function is linear. I am stumped ---- can you help??? \n" ); document.write( "
Algebra.Com's Answer #288330 by stanbon(75887)\"\" \"About 
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I have a lemonade stand and charged $1.00 per cup and sold 48 cups. When I raised the price to $2.00 per cup I only sold 27 cups. I need to write an equation for the number of cups I sold as a function of the price I charged. \"C\" would be for the number of cups and \"P\" would denote the price I charged.
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\n" ); document.write( "You have two points (1,48) and (2,27)
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\n" ); document.write( "slope = (48-27)/(1-2) = -21
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\n" ); document.write( "Form: C = mP + b
\n" ); document.write( "Substitute and solve for \"b\":
\n" ); document.write( "48 = -21(1)+b
\n" ); document.write( "b = 69
\n" ); document.write( "----
\n" ); document.write( "Equation:
\n" ); document.write( "C(P) = -21P + 69
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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