The marginal cost of producing q units is MC(q) = 2q + 10, and the marginal revenue is MR(q) = 50 - 2q. At what positive output is profit stationary?
Correct answer: B. 10 units
- A. 5 units
- B. 10 units
- C. 15 units
- D. 20 units
Explanation
Profit is stationary when marginal revenue equals marginal cost. Solving 50 - 2q = 2q + 10 gives 4q = 40, hence q = 10 units.
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