JUPEB 2021 Economics paper


  1. With reference to the relevant types of elasticity of demand, explain the terms:

    • (i) Inferior good; and (7 Marks)
    • (ii) Complementary good. (8 Marks)
  2. Discuss, with the aid of a demand and supply diagram, the effects on consumers and producers when the government introduces an indirect tax on a good. (15 Marks)

  3. With the aid of appropriate diagrams, distinguish between cost-push inflation and demand-pull inflation. (15 Marks)

  4. Write short notes on the following:

    • (i) Floating exchange rate (5 Marks)
    • (ii) Currency depreciation (5 Marks)
    • (iii) Currency devaluation (5 Marks)
  5. Explain the functions of money and its role in economic development. (15 Marks)

  6. a. Differentiate between Nominal GDP and Real GDP. (5 Marks)
    b. Explain five reasons why it is important to measure a nation's income. (10 Marks)

  7. Distinguish between the following pairs of economic concepts:

    • (i) Returns to scale and returns to size in production analysis
    • (ii) Consumer's surplus and producer's surplus
    • (iii) Average product and marginal product.
  8. a. Differentiate between Economic Growth and Economic Development. (5 Marks)
    b. List and explain FIVE major characteristics of a Less-Developed economy. (10 Marks)



Question 1: Elasticity of Demand — Inferior & Complementary Goods

(i) Inferior Good (7 Marks)

An inferior good is a good whose demand decreases as consumer income increases, giving it a negative income elasticity of demand (YED < 0).

Formula:

YED = % Change in Quantity Demanded ÷ % Change in Income

Examples: Garri, second-hand clothing, public transport.

Explanation: When income rises, consumers substitute inferior goods for superior/normal goods. For example, as income increases, consumers may shift from garri to rice. The demand curve for an inferior good shifts leftward when income rises.

Key characteristic: YED is negative.


(ii) Complementary Good (8 Marks)

A complementary good is one that is consumed jointly with another good. They have a negative cross-price elasticity of demand (XED < 0).

Formula:

XED = % Change in Quantity Demanded of Good A ÷ % Change in Price of Good B

Examples: Cars and petrol, printers and ink cartridges, bread and butter.

Explanation: When the price of one complementary good rises, demand for both goods falls. For example, if the price of cars increases, demand for petrol also decreases.

Key characteristic: XED is negative (inverse relationship between the price of one and demand for the other).


Question 2: Indirect Tax — Effects on Consumers and Producers (15 Marks)

An indirect tax is a tax levied on goods and services, paid by producers but partly shifted to consumers through higher prices.

Diagram:

Price  
  |        S2 (S + Tax)  
  |       /  
  |      / S1  
  |     /  /  
P2|.....././......  ← New consumer price  
  |    /X/  
P1|..././..........  ← Original equilibrium  
  |  / /  
Pt|./ /............  ← Producer's net price  
  | //  
  |/______________ Quantity  
     Q2   Q1  

Effects on Consumers:

  • Price rises from P1 to P2 — consumers pay more
  • Quantity demanded falls from Q1 to Q2
  • Consumer surplus is reduced
  • Consumers bear part of the tax burden (tax incidence)

Effects on Producers:

  • They receive a lower net price (Pt) after remitting tax
  • Output/supply falls from Q1 to Q2
  • Producer surplus is reduced
  • They bear the remaining portion of the tax burden

Key Conclusion:

The tax burden is shared between consumers and producers depending on the price elasticity of demand and supply. If demand is inelastic, consumers bear a greater burden; if supply is inelastic, producers bear more.


Question 3: Cost-Push vs. Demand-Pull Inflation (15 Marks)

Demand-Pull Inflation

Occurs when aggregate demand (AD) exceeds aggregate supply (AS) — "too much money chasing too few goods."

Causes: Increased government spending, consumer spending, investment, exports.

Diagram:

Price Level  
    |          AS  
    |         /  
P2  |......../  
    |    AD2/  
P1  |...../  
    |  AD1/  
    |____/_________ Real GDP  
       Y1  Y2  

AD shifts right → price level rises from P1 to P2, output rises from Y1 to Y2.


Cost-Push Inflation

Occurs when production costs rise, causing AS to shift leftward, pushing prices up while output falls (stagflation).

Causes: Rising wages, oil price increases, raw material costs, supply chain disruptions.

Diagram:

Price Level  
    |     AS2  AS1  
    |      \  /  
P2  |.......\/   
    |      /\  
P1  |...../  \  
    |  AD/    \  
    |__/__________Real GDP  
      Y2 Y1  

AS shifts left → price level rises from P1 to P2, output falls from Y1 to Y2.

Key Distinction:

Feature Demand-Pull Cost-Push
Cause Excess demand Rising production costs
Output Increases Decreases
AD/AS shift AD shifts right AS shifts left
Example Boom period Oil price shock

Question 4: Short Notes on Exchange Rate Concepts

(i) Floating Exchange Rate (5 Marks)

A floating exchange rate is a system where the value of a currency is determined by market forces of demand and supply without direct government or central bank intervention.

  • The exchange rate fluctuates freely based on trade flows, investment, and speculation
  • Example: The Nigerian Naira, US Dollar in a free market
  • Advantage: Automatic adjustment to economic shocks
  • Disadvantage: Exchange rate volatility, uncertainty for traders and investors

(ii) Currency Depreciation (5 Marks)

Currency depreciation is the gradual decline in the value of a currency relative to other currencies under a floating exchange rate system, driven by market forces.

  • It is automatic, not a government decision
  • Causes: High inflation, trade deficits, capital flight, low interest rates
  • Effect: Exports become cheaper; imports become more expensive
  • Example: If $1 = ₦800 and falls to $1 = ₦1000, the Naira has depreciated

(iii) Currency Devaluation (5 Marks)

Currency devaluation is a deliberate reduction in the official value of a currency by the government or central bank under a fixed exchange rate system.

  • It is a policy decision, unlike depreciation
  • Purpose: To boost exports, reduce trade deficits, attract foreign investment
  • Effect: Makes exports cheaper and imports more expensive
  • Example: A government officially lowers its currency from $1 = ₦400 to $1 = ₦700

Key Distinction:

Depreciation Devaluation
System Floating rate Fixed rate
Cause Market forces Government decision

Question 5: Functions of Money & Role in Economic Development (15 Marks)

Functions of Money:

1. Medium of Exchange
Money eliminates the inefficiencies of barter by serving as a universally accepted means of payment for goods and services.

2. Unit of Account / Measure of Value
Money provides a standard unit for measuring and comparing the value of goods and services (prices).

3. Store of Value
Money can be saved and retrieved in the future, allowing people to defer purchasing power over time.

4. Standard of Deferred Payment
Money enables future obligations (debts, loans) to be expressed and settled in a common unit.

5. Transfer of Value
Money facilitates easy transfer of wealth from one person or place to another.


Role of Money in Economic Development:

  • Facilitates trade and specialization: Money encourages division of labour and exchange, boosting productivity
  • Mobilizes savings and investment: Money deposited in banks is channelled into productive investments
  • Encourages entrepreneurship: Money enables capital formation and business start-ups
  • Promotes financial intermediation: Banking systems built around money channel funds from savers to investors
  • Enables fiscal policy: Governments collect taxes in money form and fund development projects
  • Supports international trade: Money in the form of foreign exchange enables cross-border transactions

Question 6

(a) Nominal GDP vs. Real GDP (5 Marks)

Feature Nominal GDP Real GDP
Definition Value of output at current prices Value of output at constant base-year prices
Inflation Not adjusted for inflation Adjusted for inflation
Usefulness Reflects current economic size Better measure of actual growth
Comparison Misleading over time Accurate for comparison over years
Example GDP rises due to price increase GDP rises only due to actual output increase

Conclusion: Real GDP is a more accurate indicator of economic growth as it removes the distorting effect of price changes.


(b) Five Reasons Why Measuring National Income is Important (10 Marks)

  1. Assessing Standard of Living: National income data (per capita income) helps compare the standard of living across countries and over time.

  2. Economic Planning and Policy Making: Governments use national income data to design fiscal and monetary policies, allocate budgets, and set development priorities.

  3. Measuring Economic Growth: By comparing national income figures over years, economists can determine whether an economy is growing, stagnant, or declining.

  4. International Comparisons: National income enables comparisons between countries, useful for foreign aid decisions, trade agreements, and investment analysis.

  5. Distribution of Income: National income data helps identify inequalities in income distribution, informing policies to reduce poverty and improve equity.

  6. (Bonus) Debt Management: It helps assess a country's debt-to-GDP ratio, indicating its capacity to repay loans.


Question 7: Distinguishing Economic Concepts

(i) Returns to Scale vs. Returns to Size

Feature Returns to Scale Returns to Size
Definition Change in output when all inputs are increased proportionately Change in output when the size/scale of plant changes
Focus Input-output relationship (long run) Physical capacity of the firm
Types Increasing, Constant, Decreasing returns to scale Small, medium, large-scale production
Context Production theory (long run) Industrial organization

Returns to scale asks: "If we double all inputs, does output more than double, exactly double, or less than double?"


(ii) Consumer's Surplus vs. Producer's Surplus

Feature Consumer's Surplus Producer's Surplus
Definition Difference between what a consumer is willing to pay and what they actually pay Difference between the price a producer receives and the minimum they would accept
Represented by Area above price line, below demand curve Area below price line, above supply curve
Benefit to Consumer Producer
Diagram Triangle above market price under demand curve Triangle below market price above supply curve

(iii) Average Product vs. Marginal Product

Feature Average Product (AP) Marginal Product (MP)
Definition Total output divided by total units of input Additional output from employing one more unit of input
Formula AP = TP ÷ L MP = ΔTP ÷ ΔL
Relationship AP rises when MP > AP; falls when MP < AP MP cuts AP at its maximum point
Use Measures productivity per worker Measures the contribution of the last unit of input

Question 8

(a) Economic Growth vs. Economic Development (5 Marks)

Feature Economic Growth Economic Development
Definition Increase in a country's real GDP or output over time Broad improvement in economic well-being, living standards, and quality of life
Scope Narrow — quantitative Broad — quantitative and qualitative
Measure GDP, GNP HDI, literacy rate, life expectancy, poverty reduction
Focus Output and income Structural transformation, equity, welfare
Sustainability May not be sustainable Aims for sustainable, inclusive progress

Conclusion: Economic growth is a necessary but not sufficient condition for economic development.


(b) Five Major Characteristics of a Less-Developed Economy (10 Marks)

  1. Low Per Capita Income: Citizens in less-developed countries (LDCs) have very low average incomes, limiting purchasing power and savings. The majority live below the poverty line.

  2. High Rate of Unemployment and Underemployment: There is widespread joblessness, especially among youth. Many people are underemployed in the informal sector, unable to find full-time productive work.

  3. Dependence on Primary Sector (Agriculture): The economy relies heavily on agriculture and raw material extraction, with little industrialization or manufacturing. This makes it vulnerable to commodity price shocks.

  4. Low Level of Technology and Capital Formation: LDCs lack advanced technology, modern machinery, and infrastructure. Low savings rates limit investment in capital goods needed for industrial development.

  5. High Population Growth Rate and Poor Human Development: LDCs typically have high birth rates, rapid population growth, poor healthcare, low literacy, and inadequate education systems — resulting in low Human Development Index (HDI) scores.

  6. (Bonus) High Dependence on Foreign Aid and External Debt: Most LDCs rely heavily on foreign loans, grants, and aid to finance development, leading to high debt burdens and limited economic sovereignty.


Note: For questions requiring diagrams (Q2, Q3), the text-based diagrams above illustrate the key shifts. In an exam setting, draw these clearly with properly labelled axes, curves, and equilibrium points.