The table below shows the output, average total cost and average revenue for a firm.
| Units of output | Average total cost (£) | Average revenue (£) |
|---|---|---|
| 20 | 30 | 45 |
| 21 | 28 | 43 |
| 22 | 27 | 42 |
| 23 | 26 | 40 |
At which one of the following levels of output will the firm maximise its profits?
20 units
21 units
22 units
23 units
156 exam-style questions on AQA A Level Economics 1.4 Production, costs and revenue, covering 1.4.1 Production and productivity, 1.4.2 Specialisation, division of labour and exchange, 1.4.3 The law of diminishing returns and returns to scale (A-level only), 1.4.4 Costs of production, 1.4.5 Economies and diseconomies of scale, 1.4.6 Marginal, average and total revenue, 1.4.7 Profit, and 1.4.8 Technological change (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.