SOLUTION: A consumer electronics company sells 6.7 million MP3 players per month at a price of $100 apiece; when the price is lowered to $80, the company sells 10.2 million players per month

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: A consumer electronics company sells 6.7 million MP3 players per month at a price of $100 apiece; when the price is lowered to $80, the company sells 10.2 million players per month      Log On


   



Question 191544: A consumer electronics company sells 6.7 million MP3 players per month at a price of $100 apiece; when the price is lowered to $80, the company sells 10.2 million players per month. How many MP3 players can the company expect to sell per month at a price of $75?
I thought I would have to figure out cost ÷ sales. I have gotten myself so confused that I don't know which way is up. I was originally trying to figure it out in a ratio format.
6.7 million/month 10.2 million/month x
$100 each $80 $75
=67,000 =127,500

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A consumer electronics company sells 6.7 million MP3 players per month at a price of $100 apiece; when the price is lowered to $80, the company sells 10.2 million players per month. How many MP3 players can the company expect to sell per month at a price of $75?
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You want a function where the number of MP3 players is the dependent variable.
You have two points: (100, 6.7 million) and (80, 10.2 million)
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slope = (10.2-6.7) million/(80-100)
slope = 3.5 million/ (-20) = -0.175 million
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intercept = ??
4.7 million = (-0.175 million)*100 + b
4.7 million = -17.5 million + b
b = 22.2 million
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Equation:
f(x) = (-0.175 million)x + 22.2 million
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Then f(75) = -0.175 million * 75 + 22.2 million
f(75) = 9.075 million (# of MP3s sold if the price is $75
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Cheers,
Stan H.