Suppose there are 20 consumers for a good and they have identical demand functions:

d(p) = 10 – 3p for any price less than or equal to 10/3 and d1(p) = 0 at any price greater than 10/3.


What is the market demand function?


d(p) = 10 – 3p if Price ≤ 10/3


d1(p) = 0 if Price > 10/3


Market Demand is total demand of all consumers


For Price ≤ 10/3


Market Demand = 20 (10 – 3p)


= 200 – 60p


For Price > 10/3


Market Demand = 20 (0)


= 0


Therefore, market demand function is


200 – 60p if Price ≤ 10/3


0 if Price > 10/3


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