1 50 Pro Imagine that a firm's total revenue and total cost functions Sol Q were TR-480-Q' 16-12+160+30 From these two equations the following table can be derived. THETR-TO TC TR 12 47 92 Su 135 176 215 167 216 Th M How much is total fixed cost? Continue the table for Q -# and 0 9 To Plot TR. TC and Tilon a diagram like Hours S. 19. It can clearly be seen from the table that profit is maximised at an output of 4. where 7/ 52 This profit-maximising output and the level of profit can be calculated without drawing up a table. The can be used. calculation involves calculus. There are two methods that Finding where MR -MC Marginal revenue can be found by differentiating the total revenue function. MR-dTR/dQ The reason is that marginal revenue is the rate of change change. of total revenue. Differentiating a function gives its role of the total cost function: Similarly, marginal cost can be found by differentiating MC- dic/8Q Differentiating TR and /C gives diR/do- 48-20-MR and dic/do -16 160- MC