# MATH

The quantity demanded for a certain brand of portable CD players is 200 units when the unit price is set at \$90. The quantity demanded is 1,200 units when the unit price is \$40. Find the demand equation.
I'm leaning toward d, but I'm not sure.

a. p = - 0.05x + 100
b. p = - 0.04x + 100
c. p = - 0.05x + 90
d. p = - 0.04x + 90

Thank you

1. 👍
2. 👎
3. 👁
1. hmmmm. It asks for demand equation, but gives answers in Inverse Price equation.

Demand equation:
demand=b-a*Price
Inverse demand equation:
P=Q/a+b where Q is demand, P price, a and b are constants.
Data
40=1200/a + b
90=200/a + b

subtract second from first
-50=1000/a
a= -20
then second equation with a
90=200/20 + b
b=80
Inverse demand equation then is
p=Q/-20 +90
p=-.05Q+90

1. 👍
2. 👎

## Similar Questions

1. ### !math (4)

The demand function for a certain brand of CD is given by p = −0.01x^2 − 0.2x + 12 where p is the unit price in dollars and x is the quantity demanded each week, measured in units of a thousand. The supply function is given by

2. ### Calculus

The demand function for Sportsman 5 X 7 tents is given by the following function where p is measured in dollars and x is measured in units of a thousand. (Round your answers to three decimal places.) p = f(x) = -0.1x^2 - x + 40

3. ### Math

The quantity demanded each month of russo Espresso Makers is 250 when the unit price is \$140; the quantity demanded each month is 1000 when th e unit price is \$110. the suppliers will market 750 expresso makers if the unit price

4. ### !math (2)

The demand function for a certain brand of CD is given by p = −0.01x^2 − 0.2x + 10 where p is the wholesale unit price in dollars and x is the quantity demanded each week, measured in units of a thousand. Determine the

1. ### Math

For the pair of supply-and-demand equations, where x represents the quantity demanded in units of 1,000 and p is the unit price in dollars, find the equilibrium quantity and the equilibrium price. p = - 2x + 15 and p = 5x + 1 a.

2. ### Economics

Suppose the price elasticity of demand for a novel translated into English is perfectly inelastic. Assume the initial price of the novel is \$24 and the quantity demanded is 222 copies per year. If the price of the novel increases

3. ### statistics

state whether the quantity described is a parameter or a statistic and give the correct notation. Correlation between height and weight for players on the 2010 Brazil World Cup team, using data from all 23 players on the roster.

4. ### Economics

When XYZ firm entered the market for good two years back, it kept the price of its product low to attract customers away from its leading competitor. The firm has now established itself and has a market share of 20 percent. The

1. ### !math (6)

The quantity demanded x (in units of a hundred) of the Mikado miniature cameras per week is related to the unit price p (in dollars) by p = −0.2x^2 + 220 and the quantity x (in units of a hundred) that the supplier is willing to

2. ### Math

For the pair of supply-and-demand equations, where x represents the quantity demanded in units of 1,000 and p is the unit price in dollars, find the equilibrium quantity and the equilibrium price. 2x + 9p - 93 = 0 and 3x - 14p +

3. ### business math

National Business Machines manufactures x model A portable printers and y model B portable printers. Each model A costs \$100 to make, and each model B costs \$150. The profits are \$40 for each model A and \$35 for each model B

4. ### Calculus

The demand function for the Luminar desk lamp is given by p = f(x) = −0.1x^2 − 0.7x + 20 where x is the quantity demanded in thousands and p is the unit price in dollars. (a) Find f '(x). (b) What is the rate of change of the