Binary Lesson 2

• Computing
• Lower Secondary (Key Stage 3)

Binary Basics: Understanding Numbers in Computing

Do now: Can you convert the following into binary
12
20
38

Do Now answers

12 in binary = 00001100

20 in binary = 00010100

38 in binary = 00100110

Learning Objectives

Aspire: Understand the 4 key binary addition rules

Conquer: Apply the binary addition rules to a question. 

Binary addtion

A computer frequently has to combine and add binary number together to solve problems.

To do this it follows 4 key rules. 

Rule number 1

0 + 0 = 0

Rule number 2

0 + 1 = 1

Rule number 3

1 + 1 = 0 carry 1

Rule number 4

1+1 + 1 = 1 carry 1

What is 0 + 0?

1. 1
2. 2
3. 00
4. 0

What is 1 + 1?

1. 0 carry 2
2. 0 carry 1
3. 01
4. 10

What is 1 + 0 ?

1. 10
2. 01
3. 1
4. 2

What is rule 4?

1. 1 carry 1
2. 1 carry 0
3. 0 carry 1
4. 12

Binary addition 

Lets use the rules 

Complete the binary addition worksheet. 

What is the number 15 in binary?

1. 0001
2. 0010
3. 1111
4. 0000

What is the number 12 in binary?

1. 1100
2. 0001
3. 1111
4. 0011

Why do we convert into binary?

1. To shorten the number
2. Its the only way the computer can understand numbers.
3. To test our skills.
4. To save time.

Extension: 

Binary conversion game 

High score receives kick board point.