0984
Number Systems
Data Representation · 4 question types
Exam Frequency Analysis
Past paper frequency (2018 to 2024)
This topic accounts for approximately 12% of your exam marks.
stable
High
Stable12%
Binary/hex conversion and binary arithmetic appear in every Paper 1. Consistently 8 to 15 marks.
Binary addition is done column by column from right to left, just like denary addition, but with only two digits and a carry rule.
The five rules of binary addition
| Sum | Result | Carry |
|---|---|---|
| 0 + 0 | 0 | none |
| 0 + 1 | 1 | none |
| 1 + 0 | 1 | none |
| 1 + 1 | 0 | carry 1 (because 1 + 1 = 10 in binary) |
| 1 + 1 + 1 | 1 | carry 1 (because 1 + 1 + 1 = 11 in binary) |
The fifth rule covers the case where two 1s and an incoming carry meet in the same column.