SOLUTION: 3.Producer will make 2,000 refrigerators available when the unit price is $330. At a unit price of $390, 6,000 refrigerators will be marketed. A) How many refrigerators will be m

They want you create a linear function of the form

    y = mx + b,

expressing the number of produced refrigerators y as the function of unit price x.


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     |   Start determine the slope coefficient m.   |
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It is the ratio of increment of y (the number of refrigerators) to the increment of unit price

    m =  =  = use your calculator = 66  = 66.666...



So, the function is 

    y - 2000 = 66.666*(x-330).      (1)


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     |   Now I am in position to answer the questions.  |
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(A)  To answer this question, simply substitute x= 450 into the formula.  You will get

         y - 2000 = 66.666*(450-330) = 66.666*120 = 8000


     which gives  y = 8000 + 2000 = 10000  refrigerators.    ANSWER




(B)  In the formula (1), we should place y = 0 and find the corresponding value of x.

     You have then


         0 - 2000 = 66.666*(x-330)

         66.666x - 66.666*330 = - 2000

         66.666x = -2000 + 66.666*330 = 19999.78

         x =  = 300  dollars.    ANSWER


      At the price of $300, the producer will stop making refrigerators.