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S4 ICT: Data and Networks – Practice Paper 3 (10 Questions)
S4 ICT: Data and Networks – Practice Paper 3 (10 Questions)
Paper 3 pushes the conversions into multimedia and capacity labels: binary and hexadecimal, uncompressed image and audio sizes, transfer time, and the difference between stepping by 1 024 and by 1 000.
Quick answer Ten items, about eighteen minutes. Items 01 to 04 cover binary, GB into MB, hexadecimal and a greyscale image; items 05 to 07 cover decimal into binary, transfer time and audio size; items 08 and 09 cover drive labels and a text file; item 10 redoes the megabyte conversion.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 questions |
| Suggested time | 18 minutes |
| Difficulty mix | Foundation 4 · Intermediate 3 · Challenge 2 · Error redo 1 |
| Chapter | Chapter: S4 ICT: Data and Networks – Tutor Lesson Plan |
| Level | S4 |
02 Questions (10 items)
- FoundationConvert the binary number 11010101 into decimal.
- FoundationHow many MB are there in 2 GB? (1 GB = 1 024 MB)
- FoundationWhat is the hexadecimal number 3A in decimal?
- FoundationA 640 by 480 pixel 8-bit greyscale image is stored uncompressed. How many KB is it?
- IntermediateWrite the decimal 90 as an 8-bit binary number.
- IntermediateA 1.5 GB file is sent over a 10 Mbps line. What is the shortest time in seconds?
- IntermediateA mono recording at 44 100 Hz and 16 bits runs for 30 seconds. How many bytes is it before compression?
- ChallengeA drive is sold as 500 GB using steps of 1 000. What size does the computer show when it steps by 1 024?
- ChallengeA plain text file holds 2 000 ASCII characters. How many KB does it take?
- Error redoA student writes that 1 MB is 1 000 KB and that 3 MB is 3 000 KB. What is the correct value in KB?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 213 | Add the columns holding a 1: 128, 64, 16, 4 and 1, which gives 213. |
| 2 | 2,048 MB | One GB is 1 024 MB, so two GB is 1 024 times 2, that is 2 048 MB. |
| 3 | 58 | Three times 16 is 48, and A stands for 10, so the value is 58. |
| 4 | 307,200 bytes, that is 300 KB | The pixel count is 307 200 at one byte each, and dividing by 1 024 gives 300 KB. |
| 5 | 01011010 | 64 plus 16 plus 8 makes 90, so those columns carry a 1 and a leading 0 pads it to eight bits. |
| 6 | 1,228.8 seconds | Turn 1.5 GB into 1 536 MB, then 12 288 Mbit, and divide by 10 Mbps to get 1 228.8 seconds. |
| 7 | 2,646,000 bytes, about 2.52 MB | Each second takes 44 100 samples of two bytes, so 88 200 bytes a second times 30 gives 2 646 000 bytes. |
| 8 | about 465.7 GB | Divide 500 billion bytes by 1 024 cubed and you get about 465.7 GB; the gap comes from the two ways of stepping. |
| 9 | 2,000 bytes, that is 1.95 KB | Each ASCII character takes one byte, so 2 000 bytes divided by 1 024 is about 1.95 KB. |
| 10 | 3,072 KB | Computers step by 1 024, so three times 1 024 gives 3 072 KB; the 1 000 step belongs to drive labelling. |
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.
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.
