9 free IGCSE Computer Science Data Representation questions written in the style of Cambridge Computer Science papers, each with its answer and mark scheme.
This topic covers Number systems, Text, sound & images, Data storage & compression. Work through the questions below, then generate a full Data Representation paper with a fresh set every time.
Generate a full Data Representation paper →A sound is recorded for 60 seconds at a sample rate of 8000 Hz and a sample resolution of 8 bits.
Calculate the file size in mebibytes (MiB). Show your working.
| Part | Answer and marking points | Marks |
|---|---|---|
| 0.458 MiB 8000 × 8 × 60 M1 ÷ 8 ÷ 1024 ÷ 1024 M1 0.458 A1 | 3 |
Add the 8-bit binary integers 10000100 and 10000111. Give your answer in 8-bit binary.
An error occurs in part (a). Identify and describe the error.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | 00001011 Working with correct carries M1 00001011 A1 | 2 |
| (b) | Overflow error: the result needs more than 8 bits, so the ninth bit is lost Overflow (error) B1 Result > 255 / needs a ninth bit that cannot be stored B1 | 2 |
Convert the denary number 112 into 8-bit binary.
Convert the binary number 10101000 into hexadecimal.
Convert the hexadecimal number AF into denary.
Give the 8-bit two’s complement representation of −5.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | 01110000 01110000 B1 | 1 |
| (b) | A8 A8 B1 | 1 |
| (c) | 175 175 B1 | 1 |
| (d) | 11111011 11111011 B1 | 1 |
The binary number 00111000 has a logical shift 1 place to the left. Give the result.
State the effect of this shift on the denary value.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | 01110000 01110000 B1 | 1 |
| (b) | multiplied by 2 × 2 B1 | 1 |
State what is meant by the term lossless compression.
State what is meant by the term lossy compression.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | Compression that reduces file size without permanently losing data Compression that reduces file size without permanently losing data B1 | 1 |
| (b) | Compression that permanently removes some data Compression that permanently removes some data B1 | 1 |
State what is meant by the term overflow error.
State what is meant by the term hexadecimal.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | An error when a result needs more bits than are available An error when a result needs more bits than are available B1 | 1 |
| (b) | A base-16 number system using the digits 0–9 and letters A–F A base-16 number system using the digits 0–9 and letters A–F B1 | 1 |
State what is meant by the term character set.
State what is meant by the term sample resolution.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | A list of characters recognised by a computer, each with a unique binary code A list of characters recognised by a computer, each with a unique binary code B2 | 2 |
| (b) | The number of bits used to store each sound sample The number of bits used to store each sound sample B1 | 1 |
An image is 640 pixels wide and 256 pixels high, with a colour depth of 8 bits.
Calculate the file size in kibibytes (KiB). Show your working.
| Part | Answer and marking points | Marks |
|---|---|---|
| 160 KiB 640 × 256 × 8 M1 ÷ 8 ÷ 1024 M1 160 A1 | 3 |
Add the 8-bit binary integers 10100010 and 00111111. Give your answer in 8-bit binary.
Describe what would happen if the result of an 8-bit addition were greater than 255.
| Part | Answer and marking points | Marks |
|---|---|---|
| (a) | 11100001 Working with correct carries M1 11100001 A1 | 2 |
| (b) | Overflow error: the result needs more than 8 bits, so the ninth bit is lost Overflow (error) B1 Result > 255 / needs a ninth bit that cannot be stored B1 | 2 |
In the 0478 syllabus, Data Representation covers Number systems, Text, sound & images, Data storage & compression.
This page has 9 Data Representation questions with answers. For more, the free generator on mentorriyaz.in builds a new Data Representation paper with a full mark scheme each time you click.
Riyaz Shaikh has mentored IGCSE, IB and A Level students for 15+ years, one-on-one, online and in Mumbai. The hardest questions on this site are the ones he uses to find a student's weak points.
Meet Riyaz →Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in