- DIN
- Objectives
- Activity 1
- Activity 2
- Plenary
⏱️ Do It Now
Copy this title into a new OneNote document:
Y10 AU – P4 – Binary Addition and 2s Compliment
Complete this table and copy it into the OneNote document:
| ⏱️ Do It Now: |
| Answer the following questions (1) What do we call the 1 or 0 in the highest place value of a binary number? (2) Put these into the correct order: MebiByte || Byte || KibiByte || Nibble || Gibibyte || Bit (3) Complete 10 conversions and screenshot your evidence into OneNote Denary ↔ Binary Practice |
🎯 Learning Objectives
(1) We are learning why and how two binary numbers are added together
(2) We will learn why 2s compliment is used by computers
(3) We will learn how to represent a negative number in 2s compliment form
📖 Activity 1 – Binary Addition
- Tab 1
- Tab 2
- Tab 3
As computers can only use 1s and 0s, they must also perform all arithmetic in binary.
In fact, computers are only capable of adding!
Computer Scientists have had to develop some ingenious methods in order to get computers to carry out subtraction, multiplication and division.
Subtraction is done by adding a positive and a negative number (we will learn how to make negative numbers today)
Division is done by repeatedly subtracting from an original number until nothing is left and multiplication is done by repeatedly adding the same number for a set amount of times.
Now its time to carry out your own binary additions: Binary Addition Practice
Remember to paste evidence of your results into OneNote
⌨️ Activity 2 – Two’s Compliment
- Tab 1
- Tab 2
- Tab 3
As you have already learned, computers are only capable of adding.
In order to carry out subtractions, computer scientists add a negative number to a positive number.
e.g. 10 + (-8) = 2
e.g. 7 + (-6) = 1
How do we represent a negative number?
Well… it’s actually quite simple;
(1) Represent the positive version of the number in binary
114 = 01110010
(2) Swap the 1s and 0s
10001101
(3) Add 1 to the number (using carry until needed)
10001110
Time to try it for yourself: Two’s Complement Practice
🎓 Plenary
In OneNote:
(1) Explain the rules of binary addition
(2) Explain the rules of Two’s compliment
