# Multiplication and Division of Length Primary 4 Math

# Detailed Student-Centered Lesson Plan

**Subject:** Mathematics

**Class:** Primary 4

**Term:** Third Term

**Week:** 5

**Topic:** Multiplication and Division of Length

**Sub-topic:** Understanding Multiplication and Division of Length

**Duration:** 60 minutes

### Behavioral Objectives:

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

- Define multiplication and division.
- Multiply lengths to find the total length.
- Divide lengths to find equal parts.
- Solve word problems involving multiplication and division of length.

### Key Words:

- Multiplication
- Division
- Length
- Perimeter
- Equal parts

### Entry Behaviour:

Pupils are familiar with basic multiplication and division.

### Learning Resources and Materials:

- Rulers
- Toy blocks
- Measuring tape
- Length charts

### Building Background / Connection to Prior Knowledge:

Pupils have previously learned basic multiplication and division with smaller numbers.

### Embedded Core Skills:

- Critical thinking
- Problem-solving
- Measurement skills

### Reference Books:

- Lagos State Scheme of Work
- Primary 4 Mathematics Textbook

### Instructional Materials:

- Flashcards
- Charts with multiplication and division examples
- Toy blocks

### Content:

Understanding multiplication and division in the context of length measurement.

### Multiplication and Division of Length

### Key Points

**Multiplication is Repeated Addition**🧮- Adding the same number many times.
- Example: 3 + 3 + 3 + 3 is the same as 3 × 4.

**Length**📏- How long something is.
- The longer side of a rectangle is called the length.
- The shorter side of a rectangle is called the breadth.

### Examples

**Example 1: Height of Toy Blocks**- Height of one block: 8 cm.
- Total height of 6 blocks: 8 cm × 6 = 48 cm.
- So, 6 blocks are 48 cm tall.

**Example 2: Perimeter of a Square**- Perimeter of the square: 48 cm.
- A square has 4 equal sides.
- Length of each side: 48 cm ÷ 4 = 12 cm.
- Each side of the square is 12 cm long.

### Exercises 📝

**Cutting a Rope**- A 40 cm rope is cut into 5 equal pieces.
- Length of each piece: 40 cm ÷ 5 = 8 cm.
- Each piece of rope is 8 cm long.
- If each piece makes a square, the side length of each square is 8 cm.

**Height of Hills**⛰️- Hill A: 120 m.
- Hill B: 2 times Hill A = 120 m × 2 = 240 m.
- Hill C: 2 times Hill B = 240 m × 2 = 480 m.
- Total height of the three hills: 120 m + 240 m + 480 m = 840 m.

**Multiplication**- Multiply 456 cm by 15.
- 456 cm × 15 = 6,840 cm.

**Division**- Divide 624 cm by 4.
- 624 cm ÷ 4 = 156 cm.

By breaking down the concepts and using examples, I hope you find multiplication and division of length easy to understand!

### Class Activity Discussion

**Q: What is multiplication?**

A: Multiplication is adding the same number many times.**Q: What is division?**

A: Division is splitting a number into equal parts.**Q: How do you find the total length of several objects?**

A: Multiply the length of one object by the number of objects.**Q: How do you find the length of one piece when cutting a rope?**

A: Divide the total length by the number of pieces.**Q: If a block is 5 cm high, what is the height of 7 blocks stacked together?**

A: 5 cm × 7 = 35 cm.**Q: What is the perimeter of a square?**

A: Add up all four sides or multiply one side by 4.**Q: If the perimeter of a square is 32 cm, how long is one side?**

A: 32 cm ÷ 4 = 8 cm.**Q: How do you find the total height of three hills if you know the height of each?**

A: Add the heights of the three hills.**Q: If Hill A is 50 m and Hill B is twice as tall, how tall is Hill B?**

A: 50 m × 2 = 100 m.**Q: How do you multiply lengths?**

A: Multiply the numbers just like normal multiplication.**Q: How do you divide lengths?**

A: Divide the numbers just like normal division.**Q: If a ribbon is 100 cm and cut into 5 pieces, how long is each piece?**

A: 100 cm ÷ 5 = 20 cm.**Q: What is the total length of 8 pencils if one pencil is 10 cm long?**

A: 10 cm × 8 = 80 cm.**Q: If a rectangle’s length is 12 cm and breadth is 4 cm, what is the perimeter?**

A: (12 cm + 4 cm) × 2 = 32 cm.**Q: If the perimeter of a square is 48 cm, how long is each side?**

A: 48 cm ÷ 4 = 12 cm.

### Presentation:

#### Step 1: Revision of Previous Topic

**Teacher’s Activities:**

- Review the previous topic on basic multiplication and division.
- Ask questions to ensure understanding.

**Learners’ Activities:**

- Answer questions from the teacher.
- Participate in discussions.

#### Step 2: Introduction of New Topic

**Teacher’s Activities:**

- Introduce the new topic: Multiplication and Division of Length.
- Explain multiplication as repeated addition and division as splitting into equal parts.
- Use examples with rulers and toy blocks.

**Learners’ Activities:**

- Listen to the teacher.
- Observe the examples.

#### Step 3: Guided Practice

**Teacher’s Activities:**

- Provide several examples of multiplying and dividing lengths.
- Allow pupils to try similar problems.
- Correct and guide pupils when necessary.

**Learners’ Activities:**

- Solve given problems.
- Share their answers and methods with the class.
- Ask questions if they do not understand.

### Teacher’s Activities:

- Engage pupils with practical examples.
- Monitor and assist pupils during practice.
- Provide feedback and corrections.

### Learners’ Activities:

- Participate actively in solving problems.
- Work in pairs or groups to discuss solutions.
- Share their findings with the class.

### Assessment:

- Observe pupils’ participation.
- Check the accuracy of their answers.
- Provide immediate feedback.

### Evaluation Questions:

- What is multiplication?
- What is division?
- If a block is 5 cm high, what is the height of 4 blocks?
- A rope of 40 cm is cut into 4 equal parts. How long is each part?
- What is the perimeter of a square with a side of 6 cm?
- If a pencil is 10 cm long, what is the total length of 5 pencils?
- Divide 56 cm by 7.
- If a rectangle’s length is 8 cm and breadth is 4 cm, what is the perimeter?
- Hill A is 50 m tall. Hill B is twice as tall. How tall is Hill B?
- What is the length of one side of a square with a perimeter of 20 cm?

### Conclusion:

**Teacher’s Activities:**

- Go around the class to check pupils’ work.
- Mark their work and provide necessary corrections.
- Summarize the lesson.

**Learners’ Activities:**

- Submit their work for marking.
- Listen to the teacher’s summary.
- Ask any remaining questions.

This lesson plan aims to engage students through hands-on activities and practical examples, ensuring they understand the concepts of multiplication and division of length.

Multiplication and Division of Mass