Binary Number System – Conversion, Addition, Subtraction, Multiplication and Division Primary 6 (Basic 6) Term 3 Week 2 Mathematics
MATHEMATICS
FIRST TERM
WEEK 2
PRIMARY 6
THEME –
PREVIOUS LESSON – Ratio and Proportion Primary 6 (Basic 6) Second Term Week 2 and Third Term Week 1 (Revision) Mathematics
TOPIC – BINARY SYSTEM
LEARNING AREA
1. Introduction
2. Conversion to Base 2
3. Conversion to Base 10
4. Addition and Subtraction of Binary Numbers
5. Multiplication and Division of Binary Numbers
6. 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. Conversion of Base 10 to Base 2.
2. Conversion of Base 2 to Base 10.
3. Perform Basic Addition and Subtraction of Binary Number.
4. Perform Basic Multiplication of Binary Number.
5. Solve Quantitative Reasoning.
ENTRY BEHAVIOURS
The pupils can perform basic mathematics operation such as addition, subtraction, multiplication and division.
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 – INTRODUCTION
Binary numbers are composed of only 0 and 1, while decimal numbers are composed of digits from 0 to 9.
ACTIVITY 1 – CONVERSION OF BASE 10 TO BASE 2
Binary is a number system that represent a base 2 number system.
This means it only has two numbers: 0 and 1.
Relationship between decimal and binary is as follows:
0 = 0₂
1 = 1₂
2 = 10₂
3 = 11₂
4 = 100₂
5 = 101₂
6 = 110₂
7 = 111₂
8 = 1000₂
9 = 1001₂
10 = 1010₂
11 = 1011₂
12 = 1100₂
13 = 1101₂
14 = 1110₂
15 = 1111₂
16 = 10000₂
17 = 10001₂
18 = 10010₂
19 = 10011₂
20 = 10100₂
Illustration,
ACTIVITY 3 – CLASS EXERCISE
Convert the following to base 2:
1. 15
2. 23
3. 78
4. 137
5. 200
SOLUTIONS
1. 15
2 | 15
2 | 7 R 1
2 | 3 R 1
2 | 1 R 1
__ | 0 r 1 ↑
15 = 1111₂
2. 23
2 | 23
2 | 11 r 1
2 | 5 r 1
2 | 2 r 1
2 | 1 r 0
_ | 0 r 1 ↑
23 = 10111₂
3. 78
2 | 78
2 | 39 r 0
2 | 19 r 1
2 | 9 r 1
2 | 4 r 1
2 | 2 r 0
2 | 1 r 0
__| 0 r 1 ↑
78 = 1001110₂
4. 137
2 | 137
2 | 68 r 1
2 | 34 r 0
2 | 17 r 0
2 | 8 r 1
2 | 4 r 0
2 | 2 r 0
2 | 1 r 0
__| 0 r 1 ↑
137 = 10001001₂
5. 200
2 | 200
2 | 100 r 0
2 | 50 r 0
2 | 25 r 0
2 | 12 r 1
2 | 6 r 0
2 | 3 r 0
2 | 1 r 1
__| 0 r 1
200 = 11001000₂
LESSON 2 – CONVERSION OF BASE 2 TO BASE 10
ACTIVITY 1 – INTRODUCTION
Decimal system is a number system that represent a 0 – 9 number system.
Relationship between binary and Decimal is as follows:
0₂ = 0
1₂ = 1
10₂ = 2
11₂ = 3
100₂ = 4
101₂ = 5
110₂ = 6
111₂ = 7
1000₂ = 8
1001₂ = 9
1010₂ = 10
1011₂ = 11
1100₂ = 12
1101₂ = 13
1110₂ = 14
1111₂ = 15
10000₂ = 16
10001₂ = 17
10010₂ = 18
10011₂ = 19
10100₂ = 20
WORKING EXAMPLE 1
1011₂
= 1 x 2³ + 0 x 2² + 1 x 2¹ + 1 x 2º
= 1 x 8 + 0 x 4 + 1 x 2 + 1 x 1
= 8 + 0 + 2 + 1
= 11
Therefore, 1011₂ = 11
WORKING EXAMPLE 2
1100₂
= 1 x 2³ + 1 x 2² + 0 x 2¹ + 0 x 2º
= 1 x 8 + 1 x 4 + 0 x 2 + 0 x 1
= 8 + 4 + 0 + 0
= 12
Therefore, 1100₂ = 12
WORKING EXAMPLE 3
1101₂
= 1 x 2³ + 1 x 2² + 0 x 2¹ + 1 x 2º
= 1 x 8 + 1 x 4 + 0 x 2 + 1 x 1
= 8 + 4 + 0 + 1
= 13
Therefore, 1101₂ = 13
WORKING EXAMPLE 4
11001₂
= 1 x 2^4 + 1 x 2³ + 0 x 2² + 0 x 2¹ + 1 x 2º
= 1 x 16 + 1 x 8 + 0 x 4 + 0 x 2 + 1 x 1
= 16 + 8 + 0 + 0 + 1
= 25
Therefore, 11001₂ = 25
WORKING EXAMPLE 5
1010110₂
= 1 x 2^6 + 0 x 2^5 + 1 x 2^4 + 0 x 2³ + 1 x 2² + 1 x 2¹ + 0 x 2º
= 1 x 64 + 0 x 32 + 1 x 16 + 0 x 8 + 1 x 4 + 1 x 2 + 0 x 1 = 64 + 0 + 16 + 0 + 4 + 2 + 0
= 86
Therefore, 1010110₂ = 86
ACTIVITY 2 – CLASS EXERCISE
Convert the following to base 10,
1. 1111₂
2. 10111₂
3. 1001110₂
4. 10001001₂
LESSON 3 – ADDITION AND SUBSTATION OF BINARY NUMBER
ACTIVITY 1 – INTRODUCTION
Addition 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 EXAMPLE 1
¹1 ¹0 ¹1 ¹ 1 1₂
+ 1 1 1 1₂
_____________
1 0 0 1 1 0₂
Therefore, 10111₂ + 1111₂ = 100110₂
WORKING EXAMPLE 2
10111₂ – 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 EXERCISE
1. 11011₂ + 10101₂
2. 1111₂ – 110011₂
3. 11011₂ – 10101₂
4. 11011₂ – 11010₂
ANSWER KEY
1. 11011₂ + 10101₂
1 1 0 1 1₂
+ 1 0 1 0 1₂
_____________
1 1 0 0 0 0₂
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 – MULTIPLICATION OF BINARY NUMBER
ACTIVITY 1 – INTRODUCTION
Multiplication is actually much similar and simpler to calculate than decimal multiplication.
MIND ON ACTIVITIES
0 x 0 = 0
0 x 1 = 0
1 x 0 = 0
1 x 1 = 1
WORKING EXAMPLE 1
10111₂ x 11₂
1 0 1 1 1₂
x 1 1₂
_____________
1 0 1 1 1₂
+ 1 0 1 1 1₂…
_____________
1 0 0 0 1 0 1₂
WORKING EXAMPLE 2
11101₂ x 101₂
1 1 1 0 1₂
x 1 0 1₂
_____________
1 1 1 0 1₂
0 0 0 0 0₂..
+ 1 1 1 0 1₂….
_____________
1 0 0 1 0 0 0 1₂
ACTIVITY 2 – CLASS EXERCISE
1. 1010₂ x 10₂
2. 1011₂ x 11₂
3. 1111₂ x 101₂
ANSWER KEY
1. 1010₂ x 10₂
1 0 1 0₂
x 1 0₂
_____________
0 0 0 0₂
+ 1 0 1 0₂..
_____________
1 0 1 0 0₂
2. 1011₂ x 11₂
1011₂
x 11₂
_____________
1 0 1 1₂
+ 1 0 1 1₂..
_____________
1 0 0 0 0 1₂
3. 1111₂ x 101₂
1 1 1 1₂
x 1 0 1₂
_____________
1 1 1 1₂
0 0 0 0₂..
+ 1 1 1 1₂….
_____________
1 0 0 1 0 1 1₂
LESSON 5 – DIVISION OF BINARY NUMBERS (OPTIONAL)
ACTIVITY 1 – INTRODUCTION
The easy way to solve division of binary numbers is to,
- Step 1 – convert the two binary numbers to base 10.
- Step 2 – Divide the dividend by the divisor.
- Step 3 – Convert the quotient back to binary number.
WORKING EXAMPLE
11001₂ ÷ 101₂
SOLUTION
Step 1 – Convert to base 10
- 11001₂ = 25
- 101₂ = 5
Step 2 – Divide dividend by divisor
25 ÷ 5 = 5
Step 3 – Convert 5 to binary.
5 = 101₂
ACTIVITY 2 – CLASS EXERCISE
1. 10010₂ ÷ 10₂
2. 10000₂ ÷ 100₂
3. 1111₂ ÷ 11₂
4. 11010₂ ÷ 1101₂
5. 11110₂ ÷ 1111₂
ANSWER KEY
1. 10010₂ ÷ 10₂
10010₂ = 18
10₂ = 2
18 ÷ 2 = 9
Therefore, 10010₂ ÷ 10₂ = 1001₂
2. 10000₂ ÷ 100₂
10000₂ = 16
100₂ = 4
16 ÷ 4 = 4
10000₂ ÷ 100₂ = 100₂
3. 1111₂ ÷ 11₂
1111₂ = 15
11₂ = 3
15 ÷ 3 = 5
Therefore, 1111₂ ÷ 11₂ = 101₂
4. 11010₂ ÷ 1101₂
11010₂ = 26
1101₂ = 13
26 ÷ 13 = 2
Therefore, 11010₂ ÷ 1101₂ = 10₂
5. 11110₂ ÷ 1111₂
11110₂ = 30
1111₂ = 15
30 ÷ 15 = 2
Therefore, 11110₂ ÷ 1111₂ = 10₂
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 displays chart showing the relationship between binary and denary numbers.
4. Teacher lets pupils study the relationship between the two forms of number.
5. Teacher uses the chart and pupil’s responses to introduce the lesson and discuss the concept of binary system.
6. Teacher guides pupils to convert numbers in binary system to denary system and vice versa.
Pupil’s Activities – Convert numbers in binary system to other bases and vice versa.
6. Teacher uses the basic conversion between binary and decimal numbers to lead the groups or pairs to add, subtract, multiply and divide binary numbers.
Pupil’s Activities – Follow the teacher’s lead to add, subtract, multiply and divide binary numbers.
6. Guides pupils to solve quantitative aptitude involving binary numbers system.
Pupil’s Activities – Solve quantitative aptitude involving binary number system.
7. Teacher summarizes each of the lesson on the board with appropriate lesson evaluation.
Pupil’s Activities –
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 – Meaning and Types of Lines, Angles and Bearing Primary 5 – Term 3 Week 2 and Primary 6 Term 3 Week 3 Mathematics
LESSON EVALUATION
As stated in the lessons.