KASNEB · FoundationEconomicsBETA — flag if wrong

Demand, Supply and Determination of Price

This topic explores the concepts of demand and supply, their determinants, and how they interact to determine market prices.

3objectives

3revision lessons

12practice questions

What you’ll learn

Aligned to the KASNEB Economics syllabus.

CF13.2.A Explain the law of demand and the law of supply.
CF13.2.B Analyze the factors that influence demand and supply.
CF13.2.C Demonstrate how equilibrium price is established in a market.

Understanding the Law of Demand and Supply

BETA — flag if wrongAI 100

The law of demand states that, ceteris paribus, as the price of a good decreases, the quantity demanded increases, and vice versa. This inverse relationship is graphically represented by a downward-sloping demand curve. Factors influencing demand include consumer preferences, income levels, and prices of related goods (substitutes and complements).

Conversely, the law of supply posits that, ceteris paribus, as the price of a good increases, the quantity supplied also increases, and vice versa. This direct relationship is illustrated by an upward-sloping supply curve. Factors affecting supply include production costs, technology, and the number of suppliers in the market.

The interaction of demand and supply determines the equilibrium price and quantity in a market. At equilibrium, the quantity demanded equals the quantity supplied. Changes in demand or supply can shift the curves, leading to a new equilibrium. For instance, an increase in demand, with supply constant, will raise both the equilibrium price and quantity. Conversely, an increase in supply, with demand constant, will lower the equilibrium price but increase the quantity sold.

Key points

Law of demand: Price down, quantity demanded up.
Law of supply: Price up, quantity supplied up.
Equilibrium price occurs where demand equals supply.
Shifts in demand/supply affect equilibrium.
Factors influencing demand include income and preferences.

Worked example

Demand and Supply Schedule

| Price (KES) | Demand (Kg) | Supply (Kg) | |--------------|-------------|--------------| | 10 | 100 | 20 | | 20 | 85 | 36 | | 30 | 70 | 53 | | 40 | 55 | 70 | | 50 | 40 | 87 | | 60 | 25 | 103 | | 70 | 10 | 120 |

Plotting Demand and Supply Curves

Demand curve slopes downward from left to right.
Supply curve slopes upward from left to right.

Determining Equilibrium

Equilibrium occurs where quantity demanded equals quantity supplied.
From the table, at KES 40, Quantity Demanded (55 Kg) equals Quantity Supplied (70 Kg), so:
- Equilibrium Price: KES 40
- Equilibrium Quantity: 55 Kg (since it’s the maximum quantity demanded at that price).

More on this topic

CF13.2.B Analyzing Factors Influencing Demand and SupplyBETA — flag if wrongAI 100

Demand and supply are fundamental concepts in economics that determine the price of goods and services in a market. The demand curve illustrates the relationship between the price of a good and the quantity demanded by consumers, while the supply curve shows the relationship between the price and the quantity supplied by producers.

Factors Influencing Demand:
1. Price of the Good: As per the law of demand, an increase in price typically leads to a decrease in quantity demanded, and vice versa.
2. Income Levels: Higher consumer income generally increases demand for normal goods, while demand for inferior goods may decrease.
3. Consumer Preferences: Changes in tastes and preferences can significantly shift demand. For example, increased health awareness may boost demand for organic foods.
4. Substitutes and Complements: The availability and price of substitute goods (e.g., tea vs. coffee) and complementary goods (e.g., printers and ink) also affect demand.

Factors Influencing Supply:
1. Production Costs: An increase in costs (e.g., wages, materials) can reduce supply, while lower costs can increase it.
2. Technology: Advancements in technology can enhance production efficiency, leading to an increase in supply.
3. Number of Suppliers: More suppliers in the market typically increase the overall supply of a good.
4. Government Policies: Taxes, subsidies, and regulations can either encourage or discourage production, thus affecting supply levels.

Understanding these factors is crucial for analyzing market dynamics and making informed business decisions.

CF13.2.C Establishing Equilibrium Price in a MarketBETA — flag if wrongAI 70

Equilibrium price is the price at which the quantity demanded by consumers equals the quantity supplied by producers. This price is determined by the interaction of supply and demand in a market. When the market is at equilibrium, there are no surpluses or shortages, and the market clears.

The demand curve typically slopes downwards, indicating that as prices decrease, the quantity demanded increases. Conversely, the supply curve slopes upwards, showing that as prices increase, the quantity supplied also increases. The point where these two curves intersect represents the equilibrium price (Pe) and equilibrium quantity (Qe).

If the price is above Pe, a surplus occurs, leading suppliers to lower prices to clear excess stock. If the price is below Pe, a shortage occurs, prompting suppliers to increase prices as demand outstrips supply.

In Kenya, understanding equilibrium price is crucial for businesses to set competitive prices and for policymakers to assess market conditions. Factors such as changes in consumer preferences, production costs, and government regulations can shift these curves, affecting the equilibrium price and quantity.

Sample KASNEB-style questions

3 of 12 questions. Beta-flagged questions are AI-drafted and pending CPA review — flag anything that looks wrong.

Q1 · MCQ · easyBETA — flag if wrongAI 100

Which of the following statements best defines the law of demand?

A.A. As the price of a good increases, the quantity demanded decreases.✓ correct
B.B. As the price of a good increases, the quantity demanded increases.
C.C. The quantity demanded is unaffected by price changes.
D.D. Demand increases with an increase in consumer income.

Q2 · MCQ · mediumBETA — flag if wrongAI 84

What effect does an increase in consumer income have on the demand for normal goods?

A.A. Demand decreases.
B.B. Demand remains constant.
C.C. Demand increases.✓ correct
D.D. Demand becomes elastic.

Q3 · SHORT ANSWER · mediumBETA — flag if wrongAI 93

Explain two main factors that can cause a shift in the supply curve.

Model answer

1. Changes in production costs: An increase in the cost of raw materials or labor can decrease supply, leading to a leftward shift of the supply curve. 2. Technological advancements: Improvements in technology can increase production efficiency, leading to an increase in supply and a rightward shift of the supply curve.

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Common questions

Explain the law of demand and the law of supply.

Law of demand: Price down, quantity demanded up.

Analyze the factors that influence demand and supply.

Demand decreases as price increases; supply increases with price.

Demonstrate how equilibrium price is established in a market.

Equilibrium price occurs where supply equals demand.