Price Determination

Grade 11 · Economics

Semester 1 | Period 1 | Week 3

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Subject: Economics

Semester: 1

Period: 1

Week: 3

School Name:

Teacher’s Name:

Subject: Economics

Grade Level: Grade 11

Week & Period: Week 3, Period I

Date:

LEARNING OBJECTIVES

By the end of the lesson, learners should be able to:

  1. Calculate price elasticity of demand using the elasticity formula.
  2. Compute price elasticity of supply.
  3. Solve income and cross elasticity problems using real data.
  4. Interpret results of elasticity calculations.

 

INSTRUCTIONAL MATERIALS

  • Sample data tables
  • Graph sheets
  • Calculators
  • Charts displaying demand/supply curves
  • Worksheets for elasticity problems

 

ANTICIPATION (Warm-Up)

Ask:
“If the price of rice increases from $10 to $12 and the quantity demanded falls from 100 to 80, how do we measure how much consumers react?”
Use this scenario to introduce elasticity calculation.

MAIN LESSON: BUILDING KNOWLEDGE


 

ILLUSTRATIVE EXAMPLES & CALCULATIONS

Interpretation: Coke and Pepsi are substitute goods.

 

ACTIVITY (Class Work)

Students are given a set of scenarios with quantities, prices, and incomes. They calculate PED, PES, YED, and XED in small groups and explain whether the result is elastic, inelastic, or unitary.

 

ASSESSMENT (Formative Questions)

  1. Calculate PED when price changes from $30 to $36 and demand falls from 90 to 70.
  2. What is the PES if supply increases from 200 to 260 when price rises from $40 to $50?
  3. Explain the difference between income elasticity and cross-price elasticity.
  4. Calculate XED if the price of coffee rises from $5 to $6 and tea demand increases from 50 to 65.
  5. If YED = -0.5, what kind of good is being discussed?

 

HOMEWORK

Solve and interpret:
A student’s allowance increases from $100 to $150. Their chocolate purchase increases from 10 to 18 bars.

  • Calculate the income elasticity.
  • Interpret the result.

 

EXPANDED NOTES

  • Elasticity is essential for setting government taxes (high on inelastic goods).
  • Luxury goods typically have high income elasticity.
  • Substitute goods have positive cross-price elasticity.

 

DIFFERENTIATION STRATEGIES

  • Graphical interpretation for visual learners.
  • Step-by-step formula breakdown for struggling students.
  • Real-life product examples for kinesthetic learners.

 

TEACHER’S REFLECTION

  • Were students able to apply formulae independently?
  • Did group discussions lead to accurate interpretations?
  • Which learners needed additional support?