Subtraction of Numbers involving Addition Mathematics Primary 1 Third Term Lesson Notes Week 3

3rd Term Mathematics Weekly Lesson Notes Primary 1 For Age 6

Subject : Mathematics

Topic :

Topic: Subtraction Involving Addition with Emphasis on the Interpretation of Addition, Subtraction, and Equal to Symbols

Grade Level: Primary 1 Duration: 45 minutes

Class : Basic 1 / Primary 1 / Grade 1

Term : Third Term

Previous Lesson 

• Counting Numbers From 1 To 180 Adding Up Two Whole Numbers with sum not more than 50 Mathematics Primary 1 Third Term Lesson Notes Week 2

Learning Objectives:

1. Understand the concept of subtraction involving addition.
2. Interpret and differentiate the symbols for addition (+), subtraction (-), and equality (=).
3. Apply the knowledge of addition and subtraction symbols to solve mathematical problems accurately.

Embedded Core Skills:

1. Numeracy Skills: Understanding addition and subtraction operations.
2. Symbolic Reasoning: Interpreting mathematical symbols (+, -, =) correctly.
3. Critical Thinking: Applying logical reasoning to solve problems.

Learning Materials:

1. Whiteboard or blackboard with markers/chalk
2. Visual aids (pictures or illustrations of addition, subtraction, and equal to symbols)
3. Manipulatives (dominos, shells, marbles, bottle tops, beans, oranges)
4. Worksheet or activity sheets for practice
5. Evaluation sheets for assessment

Content

Good morning, class! Today, we’re going to learn about a very interesting topic in mathematics: subtraction involving addition. We will also focus on understanding the symbols for addition, subtraction, and equal to. Are you all ready? Great!

Let’s start with addition. Addition is a mathematical operation that combines two or more numbers to give a total or sum. We use the “+” symbol to represent addition. For example, if we have 2 apples and we add 3 more apples, we write it as 2 + 3 = 5. Here, the “+” symbol shows that we are adding the numbers 2 and 3 to get the sum, which is 5.

Now, let’s move on to subtraction. Subtraction is another mathematical operation that helps us find the difference between two numbers. We use the “-” symbol to represent subtraction. For example, if we have 7 apples and we eat 4 of them, we write it as 7 – 4 = 3. Here, the “-” symbol shows that we are subtracting the number 4 from the number 7 to find the difference, which is 3.

Now, let’s talk about subtraction involving addition. Sometimes, we come across subtraction problems where addition can help us find the answer. Let me explain with an example. Suppose we have 10 pencils, and I give you 4 pencils. We can find out how many pencils you have left by using subtraction. We can write it as 10 – 4 = ?.

But there’s another way we can solve this problem using addition. Instead of subtracting 4 from 10, we can think of it as starting with the number 4 and adding a certain number to get 10. So, we can ask ourselves, “What number plus 4 equals 10?” Can anyone think of the number that would complete this addition sentence?

That’s right! The number that completes this addition sentence is 6. So, we can also solve 10 – 4 by doing 4 + 6 = 10. By using addition, we can find the missing number and then the difference. It’s like doing addition in reverse to find the answer to a subtraction problem.

Now, let’s look at the symbols again. The “+” symbol represents addition, the “-” symbol represents subtraction, and the “=” symbol represents equality or being equal to. It shows that the numbers or expressions on both sides of the “=” symbol have the same value. For example, 4 + 6 = 10 means that the sum of 4 and 6 is equal to 10.

In summary, subtraction involving addition allows us to find the missing number by using addition. We can use the symbols “+” for addition, “-” for subtraction, and “=” for equality or being equal to. Understanding these symbols helps us solve mathematical problems and equations correctly.

I hope you all understood the concept of subtraction involving addition and the interpretation of the addition, subtraction, and equal to symbols. Now, let’s practice some examples together to solidify our understanding.

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Evaluation

1. Example: 5 – 2 = ?

Explanation: We can think of this as starting with the number 2 and adding a certain number to get 5. What number plus 2 equals 5? The answer is 3. So, 5 – 2 is the same as 2 + 3, which equals 5.

2. Example: 9 – 6 = ?

Explanation: Instead of subtracting 6 from 9, let’s think of it as starting with the number 6 and adding a certain number to get 9. What number plus 6 equals 9? The answer is 3. So, 9 – 6 is the same as 6 + 3, which equals 9.

3. Example: 12 – 8 = ?

Explanation: We can think of this as starting with the number 8 and adding a certain number to get 12. What number plus 8 equals 12? The answer is 4. So, 12 – 8 is the same as 8 + 4, which equals 12.

4. Example: 7 – 3 = ?

Explanation: Instead of subtracting 3 from 7, let’s think of it as starting with the number 3 and adding a certain number to get 7. What number plus 3 equals 7? The answer is 4. So, 7 – 3 is the same as 3 + 4, which equals 7.

5. Example: 15 – 9 = ?

Explanation: We can think of this as starting with the number 9 and adding a certain number to get 15. What number plus 9 equals 15? The answer is 6. So, 15 – 9 is the same as 9 + 6, which equals 15.

6. Example: 20 – 14 = ?

Explanation: Instead of subtracting 14 from 20, let’s think of it as starting with the number 14 and adding a certain number to get 20. What number plus 14 equals 20? The answer is 6. So, 20 – 14 is the same as 14 + 6, which equals 20.

7. Example: 8 – 5 = ?

Explanation: We can think of this as starting with the number 5 and adding a certain number to get 8. What number plus 5 equals 8? The answer is 3. So, 8 – 5 is the same as 5 + 3, which equals 8.

8. Example: 16 – 10 = ?

Explanation: Instead of subtracting 10 from 16, let’s think of it as starting with the number 10 and adding a certain number to get 16. What number plus 10 equals 16? The answer is 6. So, 16 – 10 is the same as 10 + 6, which equals 16.

9. Example: 11 – 7 = ?

Explanation: We can think of this as starting with the number 7 and adding a certain number to get 11. What number plus 7 equals 11? The answer is 4. So, 11 – 7 is the same as 7 + 4, which equals 11.

10. Example: 13 – 6 = ?

Explanation: Instead of subtracting 6 from 13, let’s think of it as starting with the number 6 and adding a certain  number to get 13. What number plus 6 equals 13? The answer is 7. So, 13 – 6 is the same as 6 + 7, which equals 13.

I hope these examples helped you understand subtraction involving addition and the interpretation of the addition, subtraction, and equal to symbols. Remember, you can use addition to find the missing number and then solve the subtraction problem. Keep practicing, and you’ll become experts in no time

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1. 6 – 2 = ___ a) 2 b) 4 c) 6
2. 9 – 5 = ___ a) 2 b) 4 c) 9
3. 12 – 7 = ___ a) 5 b) 7 c) 12
4. 10 – 4 = ___ a) 6 b) 10 c) 4
5. 15 – 8 = ___ a) 7 b) 8 c) 15
6. 18 – 9 = ___ a) 9 b) 18 c) 27
7. 7 – 3 = ___ a) 3 b) 4 c) 7
8. 14 – 6 = ___ a) 8 b) 14 c) 20
9. 20 – 12 = ___ a) 12 b) 20 c) 32
10. 17 – 5 = ___ a) 5 b) 12 c) 17

Remember to carefully consider the concept of subtraction involving addition and choose the correct option that represents the missing number. Good luck!

Lesson Plan Presentation

Presentation:

1. Introduction (5 minutes): a. Greet the students and engage them in a short discussion about addition and subtraction. b. Explain that today we will learn about subtraction involving addition and the symbols used to represent these operations.
2. Concept Explanation (10 minutes): a. Introduce the concept of subtraction involving addition using relatable examples. b. Explain that subtraction involving addition is a way of finding a missing number by using addition. c. Use visual aids or manipulatives to demonstrate how to solve subtraction problems using addition.
3. Interpretation of Symbols (5 minutes): a. Present the symbols for addition (+), subtraction (-), and equality (=). b. Explain the meanings of each symbol and how they relate to the operations. c. Provide examples and encourage students to identify and interpret the symbols correctly.
4. Teacher’s Activities (10 minutes): a. Demonstrate solving subtraction involving addition problems on the board using manipulatives and symbols. b. Encourage student participation by asking questions and guiding them through the process. c. Provide step-by-step explanations of the calculations and symbol usage.
5. Learners’ Activities (10 minutes): a. Distribute worksheets or activity sheets to each student. b. Instruct students to solve the subtraction involving addition problems on their own, using manipulatives or symbols as needed. c. Circulate around the classroom, providing assistance and guidance to individual students.
6. Assessment (5 minutes): a. Distribute evaluation sheets to assess students’ understanding of the topic. b. The evaluation may consist of both written and practical components. c. Evaluate students’ ability to interpret symbols and solve subtraction involving addition problems accurately.
7. Ten Evaluation Questions:
   1. What is subtraction involving addition?
   2. What symbol represents addition?
   3. What symbol represents subtraction?
   4. What symbol represents equality?
   5. Solve the following problem using subtraction involving addition: 8 – 3 = ?
   6. Explain the process of solving subtraction involving addition using an example.
   7. Demonstrate the addition symbol using manipulatives or symbols.
   8. How do you interpret the subtraction symbol in a mathematical problem?
   9. Complete the equation: 7 + ___ = 12
   10. Solve the following problem: 15 – 9 = ?
8. Conclusion (2 minutes): a. Summarize the key points discussed during the lesson. b. Highlight the importance of understanding addition, subtraction, and equal to symbols for solving mathematical problems accurately.
9. Homework Assignment (3 minutes): a. Assign a few practice problems related to subtraction involving addition, using symbols, and interpretation.
10. b. Remind students to review the symbols and concepts covered in class .

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Note: The lesson plan can be adjusted based on the specific needs and abilities of the students. Additional time can be allocated for hands-on activities using manipulatives, if required, to reinforce the concept of subtraction involving addition and the interpretation of symbols.