Computer Science 9618/33 Oct/Nov 2025 past paper

Grade thresholds for 9618/33 Oct/Nov 2025

The minimum raw marks Cambridge set for each grade on this component (out of 75). Thresholds change every session and variant, so always compare your score with the paper you actually sat.

Topics in this paper

Which syllabus chapters 9618/33 Oct/Nov 2025 tested, by marks. Each chapter links to every past-paper question on it.

Questions in 9618/33 Oct/Nov 2025

1. Question 1Data Types and Structures · 8 marks

   (a) An enumerated data type, Spectrum, is required to hold the names of colours. (i) Write the pseudocode statement for the type declaration of Spectrum to hold the names of the colours available: Red, Orange, Yellow, Green, Blue, Indigo, Violet. …

2. Question 2Data Representation · 6 marks

   Numbers are stored in a computer system using binary floating‑point representation with: • 12 bits for the mantissa • 4 bits for the exponent • two’s complement form for both the mantissa and the exponent • 2 bytes in total. …

3. Question 3Communication and internet technologies · 4 marks

   Describe how packet switching is used to pass messages across a network. Do not include checking for completeness and resending packets in your answer.

4. Question 4Communication and internet technologies · 6 marks

   Identify and describe three protocols that are used in the Application Layer of the TCP/IP protocol suite. Protocol 1 Description Protocol 2 Description Protocol 3 Description

5. Question 5System Software (A Level) · 4 marks

   (a) State the purpose of multi‑tasking. (b) Explain how an operating system ensures that multi‑tasking operates efficiently.

6. Question 6Hardware and Virtual Machines · 8 marks

   (a) The Karnaugh map (K‑map) represents a logic circuit with four inputs. AB CD …

7. Question 7Data Types and Structures · 9 marks

   (a) Outline the process of optimisation during the compilation of a program. (b) Write the Reverse Polish Notation (RPN) for the given infix expression: …

8. Question 8Data Types and Structures · 5 marks

   Calculate the shortest distance between the Start node and each of the nodes in the graph using Dijkstra’s algorithm. Show your working on the graph or in the working space. Write your answers in the table provided. …

9. Question 9Security (A Level) · 4 marks

   A company requires a digital certificate to ensure the authenticity of its online communications. Outline the process followed to acquire a digital certificate.

10. Question 10Data Types and Structures · 6 marks

    A stack, StackArray, is to be implemented using pseudocode, to store a maximum of 100 string items in an appropriate array. Declarations are required so that the stack has a beginning, an end and a maximum size. An array is …

11. Question 11Algorithm Design and Problem-solving · 3 marks

    Describe when the use of recursion would be beneficial and give an example. Description Example

12. Question 12System Software (A Level) · 5 marks

    An exception can occur when running a program. (a) Explain what is meant by an exception. (b) Identify one example of an exception and give one reason why the exception may cause a problem. Example Reason

13. Question 13Processor Fundamentals · 7 marks

    The table shows assembly language instructions for a processor that has one register, the Accumulator (ACC). Label Instruction Explanation Opcode Operand LDM #n Load the number n to the ACC LDD <address> Load the contents of the location at the …

Other Computer Science papers from Oct/Nov 2025

• 9618/11 Theory fundamentals
• 9618/12 Theory fundamentals
• 9618/13 Theory fundamentals
• 9618/21 Problem-solving & programming
• 9618/22 Problem-solving & programming
• 9618/23 Problem-solving & programming
• 9618/31 Advanced theory
• 9618/32 Advanced theory
• 9618/41 Practical programming
• 9618/42 Practical programming
• 9618/43 Practical programming