# Binary Number System – Addition and Subtraction of Binary Numbers Primary 5 (Basic 5) Term 3 Week 9 Mathematics

### MATHEMATICS

THIRD TERM

WEEK 9

PRIMARY 6

THEME – NUMBERS AND NUMERATION

PREVIOUS LESSON – Binary Number System – Conversion of Base 2 to Base 10 | Conversion of Base 10 to Base 2 Primary 5 (Basic 5) Term 3 Week 8 Mathematics

**TOPIC – BINARY SYSTEM**

**LEARNING AREA**

1. Introduction

2. Addition of Binary Numbers

3. Subtraction of Binary Numbers

4. Lesson Evaluation and Weekly Assessment (Test)

### LEARNING OBJECTIVES

By the end of the lesson, most of the pupils should have attained the following objectives –

1. Perform Basic Addition and Subtraction of Binary Number.

2. Solve Quantitative Reasoning.

### ENTRY BEHAVIOURS

The pupils can perform basic mathematics operation such as addition and subtraction.

### INSTRUCTIONAL MATERIALS

The teacher will teach the lesson with the aid of chart showing relationships between binary (base 2) and decimal (base 10).

**METHOD OF TEACHING **

Choose a suitable and appropriate methods for the lessons.

Note – Irrespective of choosing methods of teaching, always introduce an activities that will arouse pupil’s interest or lead them to the lessons.

**REFERENCE MATERIALS**

1. Scheme of Work

2. 9 – Years Basic Education Curriculum

3. Course Book

4. All Relevant Material

5. Online Information

### CONTENT OF THE LESSON

**LESSON 1 – ADDITION OF BINARY NUMBERS **

ACTIVITY 1 – INTRODUCTIONAddition and subtraction are much like your normal everyday addition (decimal addition), except that it carries on a value of 2 instead of a value of 10.

For example,

8 + 2 = 10 (decimal number), corresponding value in binary is 1₂ + 1₂ = 10.

WORKING EXAMPLE¹1 ¹0 ¹1 ¹ 1 1₂

+ 1 1 1 1₂

_____________

1 0 0 1 1 0₂

Therefore,

10111₂ + 1111₂ = 100110₂

ACTIVITY 2 – CLASS EXERCISE1. 11011₂ + 10101₂

2. 1111₂ + 110011₂

3. 11011₂ + 10101₂

4. 11011₂ + 11010₂

**LESSON 2 – REVISION OF LESSON 1 **

Revision with more working examples and exercises.

### LESSON 3 – SUBSTATION OF BINARY NUMBER

WORKING EXAMPLE10111₂ – 1111₂

1º 0² 1 1 1₂

– 1 1 1 1₂

_____________

1 0 0 0₂

Therefore,

10111₂ – 1111₂ = 1000₂

Note – 1 borrow from the next digit is equal to 2 just as in decimal, the one you borrow from the next digit is equal to 10.

ACTIVITY 2 – CLASS EXERCISE1. 11011₂ – 10100₂

2. 1111₂ – 110011₂

3. 11011₂ – 10101₂

4. 11011₂ – 11010₂

ANSWER KEY1. 11011₂ – 10100₂

1 1 0 1 1₂

– 1 0 1 0 0₂

_____________

1 1 1₂

2. 1111₂ – 1011₂

1 1 1 1₂

– 1 0 1 1₂

_____________

1 0 0₂

3. 11011₂ – 10101₂

1 1 0 1 1₂

– 1 0 1 0 1₂

_____________

1 1 0₂

4. 11011₂ – 11010₂

11011₂

– 11010₂

_____________

1₂

**LESSON 4 – REVISION OF LESSON 3**

Revision with more working examples and exercises.

**LESSON 5 – REVISION, LESSON EVALUATION AND WEEKLY ASSESSMENT (TEST) **

**PRESENTATION**

To deliver the lesson, the teacher adopts the following steps:

1. To introduce the lesson, the teacher revises the previous lesson. Based on this, he/she asks the pupils some questions;

2. Teacher organizes pupils in groups or pairs depending on the size of the class.

3. Teacher uses addition and subtraction of decimal numbers to introduce the lesson – addition and subtraction of binary numbers.

Pupil’s Activities – Pay attention to the lesson introduction.

4. Teacher uses the basic conversion between binary and decimal numbers to lead the groups or pairs to add and subtract of binary numbers.

Pupil’s Activities – Follow the teacher’s lead to add and subtract, binary numbers.

5. Guides pupils to solve quantitative aptitude involving binary numbers system.

Pupil’s Activities – Solve quantitative aptitude involving binary number system.

6. Teacher summarizes each of the lesson on the board with appropriate lesson evaluation.

Pupil’s Activities – Participate actively in the summary of the lesson by responding correctly to the questions and write as instructed.

**CONCLUSION**

To conclude the lesson for the week, the teacher revises the entire lesson and links it to the following week’s lesson.

Next Lesson –

**LESSON EVALUATION**

As stated in the lessons.