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S3 ICT: Binary and Hexadecimal Data Representation (Paper 4: misconception drill)
S3 ICT: Binary and Hexadecimal Data Representation (Paper 4: misconception drill)
S3 ICT binary and hexadecimal paper 4, misconception drill on place values, digit by digit misreading, twos complement and overflow.
Direct answers Answers in order: 1100, 16, 9, 255, 180, 0010 1101, minus 1, 4, it becomes 00 through overflow, and 101 equals 5.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 20 |
| Difficulty mix | Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1 |
| Chapter | Chapter: S3 ICT: Binary and Hexadecimal Data Representation |
| Level | S3 |
02 Questions (10 items)
- FoundationWrite denary 12 as a 4 bit binary number.
- FoundationWhat is the denary value of hexadecimal 10?
- FoundationWhat is the denary value of binary 1001?
- IntermediateWhat is the denary value of binary 1111 1111?
- IntermediateWhat is the denary value of hexadecimal B4?
- IntermediateWrite denary 45 as an 8 bit binary number.
- ChallengeWhich value does the 8 bit twos complement pattern 1111 1111 represent?
- ChallengeIn binary 100, what is the place value of the 1?
- ChallengeWhat happens when 1 is added to the 8 bit hexadecimal FF?
- Error redoA student reads binary 101 as one hundred and one. What is wrong?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 1100 | 8 plus 4 gives 12, so the answer is 1100 and not 1010. |
| 2 | 16 | 1 times 16 plus 0 gives 16, not 10. |
| 3 | 9 | 8 plus 1 gives 9, and 1001 must not be read as one thousand and one. |
| 4 | 255 | All eight bits are 1, which equals 2 to the power 8 minus 1. |
| 5 | 180 | 11 times 16 plus 4 gives 180. |
| 6 | 0010 1101 | 32 plus 8 plus 4 plus 1 gives 45, padded with leading zeros to eight bits. |
| 7 | Minus 1 | All ones in twos complement means minus 1, not 255. |
| 8 | 4 | The third position from the right is worth 2 to the power 2, that is 4. |
| 9 | It becomes 00, because the carry beyond eight bits is discarded | 255 plus 1 needs nine bits, so the carry past the eighth bit cannot be stored, which is overflow. |
| 10 | Binary 101 is 4 plus 1, that is 5 | Binary place values are 4, 2 and 1 rather than hundreds, tens and units; the same slip turns 1100 into one thousand one hundred. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
Expand binary by place value into denary first, then group four bits per hexadecimal digit; check for twos complement when negatives appear and confirm the answer stays within the bit width.Tutor Registration →
Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.