The Pear company sells Iphones. The cost to manufacture x pPhones is C(x) = -27x²+48000x+18460 dollars (this includes overhead costs and production costs for each pPhone). If the company sells x pPhones for the maximum price they can fetch, the revenue function will be R(x) = -3x²+168000x dollars. How many phones should the Pear company produce and sell to maximize profit? (Remember profit=revenue cost)

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