IBDP Computer Science A1.2 Data representation and computer logic SL Paper 1 - New Syllabus
Question
A binary number is held in the following 12-bit register:
| 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 0 | 1 | 0 |
(a) State the hexadecimal representation of this binary number. [1]
(b) State how many different binary numbers can be represented in a 12-bit register. [1]
Most-appropriate topic code (CED):
• TOPIC A1.2: Data representation and computer logic — parts (a) and (b)
▶️ Answer/Explanation
(a)
Group the 12-bit binary number into groups of four bits:
1111 0011 1010Each group corresponds to one hexadecimal digit:
| Binary | Hexadecimal |
|---|---|
| 1111 | F |
| 0011 | 3 |
| 1010 | A |
Therefore, the hexadecimal representation is F3A.
(b)
Each bit has two possible values, 0 or 1. Therefore, a 12-bit register can represent:
2^12 = 4096Therefore, 4096 different binary numbers can be represented.
Award [1] for each correct answer.
