Definitions of total revenue (TR) and average revenue (AR)

Microeconomic Decision‑Makers: Firms' Costs, Revenue and Objectives

Definitions of Total Revenue (TR) and Average Revenue (AR)

Total Revenue (TR) is the total amount of money a firm receives from selling its goods or services.



Formula:


\$TR = P \times Q\$



Where:

  • \$P\$ = price per unit (in £ or $)
  • \$Q\$ = quantity sold (in units)

Average Revenue (AR) is the revenue earned per unit of output sold.



Formula:


\$AR = \frac{TR}{Q}\$



In perfect competition, AR equals the market price (P).

Lemonade Stand Analogy 🍋

Imagine you run a lemonade stand.



Scenario: You sell 50 cups of lemonade at £2 each.



Calculations:

  • TR = 50 × £2 = £100
  • AR = £100 ÷ 50 = £2 per cup


So, TR is the total money you collect (£100), and AR is the average money you get per cup (£2).

Exam Tips 📚

  1. Remember the core formulas: \$TR = P \times Q\$ and \$AR = \frac{TR}{Q}\$.
  2. In perfect competition, AR = P. Use this to simplify calculations.
  3. When given a graph of price and quantity, you can find TR by multiplying the price on the y‑axis by the quantity on the x‑axis.
  4. Check units: TR is in money (£ or $), AR is in money per unit.
  5. Use the analogy of a lemonade stand or a bakery to explain concepts to peers.

ConceptFormulaExample (50 units @ £2)
Total Revenue (TR)\$TR = P \times Q\$\$TR = 2 \times 50 = £100\$
Average Revenue (AR)\$AR = \frac{TR}{Q}\$\$AR = \frac{100}{50} = £2\$