Revenue, cost, and profit functions:-
A company manufactures 10- and 3-speed bicycles. The weekly demand and cost equations are
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where $p is the price of a 10-speed bicycle, $q is the price of a 3-speed bicycle, x is the weekly demand for 10-speed bicycles, y is the weekly demand for 3-speed bicycles, and C(x, y) is the cost function.
Find the weekly revenue function R(x, y) and the weekly profit function P(x, y). Evaluate R(10, 15) and P(10, 15).