SOLUTION: Please help me solve this problem: Suppose you have a lemonade stand, and when you charge $2 per cup of lemonade you sell 120 cups. But when you raise your price to $3 you only sel

Algebra ->  Linear-equations -> SOLUTION: Please help me solve this problem: Suppose you have a lemonade stand, and when you charge $2 per cup of lemonade you sell 120 cups. But when you raise your price to $3 you only sel      Log On


   



Question 277463: Please help me solve this problem: Suppose you have a lemonade stand, and when you charge $2 per cup of lemonade you sell 120 cups. But when you raise your price to $3 you only sell 60 cups. Write an equation for the number of cups you sell as a function of the price you charge. Denote "C" for the number of cups, and "P" for the price you charge. Assume the function is linear.
Continuing our lemonade stand question:
We all know that local revenue (TR) is a function of the price we charge (P) multiplied by the item quantity sold (in our case-Cups),i.,e.,TR=Price*Cups.
Please write the equation for your TR by inputting your answer from the function you have calculated. What price would you maximize your TR?

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Suppose you have a lemonade stand, and when you charge $2 per cup of lemonade you sell 120 cups. But when you raise your price to $3 you only sell 60 cups. Write an equation for the number of cups you sell as a function of the price you charge. Denote "C" for the number of cups, and "P" for the price you charge. Assume the function is linear.
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You have two points relating price and cups sold: (2,120) and (3,60)
Equation you want: C = mp + b where p is price and C is # of cups.
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slope = m = (120-60)/(2-3) = -60
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60 = -60*3 + b
b = 4*60
b = 240
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Equation: # of cups sold = -60p + 240
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Continuing our lemonade stand question:
We all know that local revenue (TR) is a function of the price we charge (P) multiplied by the item quantity sold (in our case-Cups),i.,e.,TR=Price*Cups.
Please write the equation for your TR by inputting your answer from the function you have calculated. What price would you maximize your TR?
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Total Revenue = -60p^2 + 240p
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This is a quadratic equation with a = -60 and b = 240
Maximum occurs when p = -b/2a = -240/(-120) = 2
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Maximum sales occurs when the price is $2.
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Cheers,
Stan H.