Percentages : Meaning and Conversion of Percentages to Decimals Mathematics Primary 5 Second Term Lesson Notes Week 3

Subject: Mathematics
Class: Primary 5
Term: First Term
Week: 3
Topic: Converting Percentages to Decimal
Sub-topic: Understanding the relationship between percentages and decimals
Duration: 40 minutes

Behavioural Objectives:

• Students will be able to convert percentages to decimals correctly.
• Students will understand the concept of fractions and decimals in percentages.

Key Words: Percentages, Decimals, Conversion, Fractions, Percentage Symbol.

Entry Behaviour:
Students should be familiar with basic fractions and have a basic understanding of percentages.

Learning Resources and Materials:

• Lagos State Scheme of Work for Primary 5 Mathematics
• Whiteboard and markers
• Flashcards with percentages and their decimal equivalents
• Worksheets for practice

Building Background/Connection to Prior Knowledge:
Review with students what percentages are and their representation out of 100. Connect this to fractions and explain how decimals are related to fractions.

Embedded Core Skills:
Numeracy, Problem-solving, Critical Thinking.

Instructional Materials:

• Introduction to percentages and their meaning.
• Examples of converting percentages to decimals.
• Practice exercises for students.

Content/Presentation:

Topic: Change 70% to decimal

1. Understand the concept:
   • Percentages are a way of expressing a fraction of 100. So, 70% means 70 out of 100.
2. Convert 70% to decimal:
   • Step 1: Divide the percentage by 100.
   • Step 2: Remove the percentage symbol.
3. Example:
   • Percentage: 70%
   • Conversion:
     • 70100=0.7010070​=0.70
     • Therefore, 70% as a decimal is 0.70 or 0.7

Changing Percentages to Decimals:

1. What does it mean to convert a percentage to a decimal?
   • Converting a percentage to a decimal means expressing the percentage as a number between 0 and 1.
2. How do you convert 70% to a decimal?
   • Divide 70 by 100: 70100=0.7010070​=0.70
3. What is 70% as a decimal?
   • 70% as a decimal is 0.70.
4. Can you explain the process of converting a percentage to a decimal in simple terms?
   • To convert a percentage to a decimal, divide the percentage value by 100 and remove the percentage symbol.
5. What is the relationship between percentages and decimals?
   • Percentages are fractions of 100, and decimals are fractions of 1. Converting between them helps in mathematical calculations and comparisons.
6. What happens if you convert 100% to a decimal?
   • Converting 100% to a decimal results in 1, as 100% represents the whole (or 1) of something.
7. Why is it important to understand how to convert percentages to decimals?
   • Understanding this conversion helps in various mathematical operations, such as calculations involving taxes, discounts, interest rates, and more.
8. What is the decimal form of 50%?
   • Converting 50% to a decimal yields 0.50.
9. How do you convert percentages ending in 0 to decimals?
   • Simply remove the percentage symbol, as in converting 80% to 0.80.
10. Is there a quick method to convert common percentages to decimals?
    • Yes, you can move the decimal point two places to the left to convert percentages to decimals quickly. For example, 25% becomes 0.25, 40% becomes 0.40, and so on.

Evaluation :

1. Convert 80% to a decimal: ___ a) 0.8 b) 0.80 c) 8 d) 0.008
2. What is 50% as a decimal? ___ a) 0.05 b) 0.5 c) 5 d) 50
3. Change 25% to decimal: ___ a) 2.5 b) 0.025 c) 0.25 d) 25
4. If you convert 100% to a decimal, you get ___. a) 100 b) 1 c) 10 d) 0.01
5. Convert 60% to a decimal: ___ a) 6 b) 0.6 c) 0.06 d) 60
6. What is the decimal form of 35%? ___ a) 0.35 b) 0.035 c) 0.0035 d) 35
7. Changing 90% to decimal gives ___. a) 0.90 b) 0.09 c) 9 d) 90
8. Convert 15% to decimal: ___ a) 0.015 b) 0.15 c) 1.5 d) 15
9. 10% as a decimal is ___. a) 0.010 b) 0.1 c) 10 d) 1
10. The decimal form of 75% is ___. a) 0.075 b) 0.75 c) 7.5 d) 75
11. If you convert 5% to a decimal, you get ___. a) 0.005 b) 0.05 c) 0.5 d) 5
12. What is 20% as a decimal? ___ a) 0.02 b) 0.2 c) 2 d) 20
13. Change 45% to decimal: ___ a) 0.0045 b) 0.045 c) 0.45 d) 4.5
14. The decimal form of 30% is ___. a) 0.003 b) 0.03 c) 0.3 d) 3
15. Converting 3% to decimal gives ___. a) 0.03 b) 0.3 c) 3 d) 0.003

Content/Presentation: Step 1: The teacher revises the previous topic which was understanding basic fractions and percentages.

Step 2: The teacher introduces the new topic, explaining that percentages can be converted to decimals by dividing by 100.

Step 3: The teacher allows the pupils to give their own contributions and corrects them when necessary, providing feedback to ensure understanding.

Teacher’s Activities:

• Presenting examples of converting percentages to decimals.
• Facilitating class discussions.
• Providing guidance and feedback during practice exercises.

Learners Activities:

• Listening to the teacher’s explanations.
• Participating in class discussions.
• Practicing converting percentages to decimals individually and in groups.

Assessment:

• Observing students’ participation and understanding during discussions.
• Reviewing students’ completed practice exercises for accuracy.

Ten Evaluation Questions Related to the Topic:

1. What is 50% as a decimal?
2. Convert 75% to decimal.
3. Explain how to convert percentages to decimals.
4. What is the decimal form of 20%?
5. Convert 30% to decimal.
6. Why do we divide by 100 when converting percentages to decimals?
7. What happens if you convert 100% to a decimal?
8. What is 10% as a decimal?
9. Give an example of converting a percentage to a decimal.
10. How can you check if your conversion of a percentage to a decimal is correct?

Conclusion:
The teacher goes round to mark students’ work and provides necessary feedback and corrections. Reinforce key concepts and encourage students to practice converting percentages to decimals at home for mastery.