Computational skills

​Discover new features in Lessons!
Finish all phases of “I-do ; We-do ; You-do” with Quizizz

​Install Google Slides Extension

​You can also create lessons directly on Google Slides using “Quizizz Extension”.
Read more about it here

Open Ended

What is abstraction? (think of definition, purpose and example)

​Replace this with a header

It simplifies a real-world object or scenario by removing unnecessary details.
To solve a specific problem effectively while maintaining computational efficiency.
London Tube map: Only details relevant to journey planning are kept.
Flight simulator: Includes properties like weight but ignores irrelevant details like upholstery.
Identify the essential details for the problem being solved. Discard irrelevant or non-impactful details.

Types of abstractions

Abstraction by generalisation
Procedural abstraction
functional abstraction
Data abstractions

​How to attempt questions on abstraction

1. read the question carefully.

2. focus on the core concept of simplification and relevance.

3. define abstraction clearly

4. give examples

5. justify why these choices are made based on the purpose in the context.

Multiple Choice

What is abstraction?

• A detailed representation of all features of an object

• The process of removing unnecessary details to simplify a model

• A way of physically representing an object in a computer system

• The process of adding more features to make a model comprehensive

Multiple Choice

Why are unnecessary details removed in abstraction?

• To prioritize irrelevant information

• To ensure every detail is accurately represented

• To reduce computational complexity and focus on solving a problem

• The process of adding more features to make a model comprehensive

Multiple Choice

Which of the following is an example of abstraction?

• A weather forecasting model that includes wind, humidity, and temperature

• A 3D rendering of a car with every single component modeled

• . A video game that mimics real-world physics in every detail

• A Tube map that simplifies distances but shows station connectivity

Multiple Choice

What determines what is included in an abstraction?

• The designer's personal preference

• The hardware specifications of the system

• The problem being solved and the required degree of accuracy

• The aesthetics of the representation

Multiple Choice

In a flight simulator why is the weight of the plane represented while seat upholstery details are not?

• Weight impacts handling, while upholstery details are irrelevant to simulation goals

• Upholstery details are too difficult to simulate

• Weight is easier to model than upholstery details

• The system designer forgot to include upholstery details

Open Ended

Explain the concept of abstraction using the example of the London Tube map. (3 marks)

Model answer (3 marks)

abstraction involves simplifying a system by removing unnecessary details to focus on what is essential for solving a particular problem. The London Tube map is a good example. It removes irrelevant details such as the actual geographical distances between stations or the exact of the city. Instead, it focuses on showing the connectivity between stations and lines, making it easier to plan journeys. This allows users to navigate the transport system without being distracted by unnecessary information.

Open Ended

Discuss how abstraction is applied in a flight simulator and explain why some details are included while others are omitted. ( 4 marks)

Model answer (4 marks)

Abstraction in a flight simulator involves simplifying real-world planes to include only the details necessary for simulating flight accurately. Essential properties like the plane's weight, dimensions, and aerodynamic features are included because they directly affect its handling and performance. However, irrelevant details, such as the material used to upholster the seats or the specific brand of in-flight entertainment, are omitted because they do not impact the simulation's purpose of training pilots or analyzing flight. By focusing only on critical elements, the simulator becomes both efficient and effective in meeting its objectives.

Open Ended

How would you explain what thinking procedurally is?

Thinking procedurally

The procedural programming paradigm is where program code is divided up into procedures, which are discrete blocks of code that carry out a single task. Procedures, also called subroutines or functions, contain a series of computational steps to be carried out in the order specified by the programmer.

Multiple Choice

What is the main purpose of a structure chart in program development?

• To represent the sequence of operations in a flowchart.

• To decompose a program into its sub-procedures and their relationships.

• To display pseudocode in a graphical form.

• To identify hardware components in a computing system.

Multiple Choice

What is the role of a sub-procedure in a program?

• To visualize the program flow in a diagram.

• To replace the need for inputs and outputs.

• To divide a program into smaller, reusable components.

• To define global variables.

Multiple Choice

Which of the following best represents the use of parameters in sub-procedures?

• Parameters pass data into and out of a sub-procedure.

• Parameters are optional details that can be added to enhance readability.

• Parameters determine the sequence of operations in a program.

• Parameters are preconditions for program execution.

Multiple Choice

In a flowchart, what shape is used to represent a decision point?

• Rectangle

• Diamond

• Oval

• Parallelogram

Multiple Choice

Why is it important to write pseudocode before coding a program?

• To reduce the length of the final program.

• To create a visual representation of program logic.

• To plan and structure the program's logic before implementation.

• To ensure that flowcharts are accurate.

Multiple Choice

What should you consider when designing sub-procedures?

• The aesthetics of the structure chart.

• The size of the variables used.

• The programming language being used.

• The specific tasks to be handled and how parameters are passed.

Multiple Choice

Which of the following is a key difference between pseudocode and flowcharts?

• Pseudocode is a textual description of algorithms, while flowcharts are graphical representations.

• Pseudocode uses diagrams, while flowcharts use text.

• Flowcharts represent decision-making processes, while pseudocode does not.

• Flowcharts are used in program debugging, pseudocode is not.

Multiple Choice

What is the purpose of putting steps into the correct order in an algorithm?

• To minimize the number of variables.

• To reduce the need for debugging.

• To simplify the structure diagram.

• To ensure the program logic is correct and functional.

Open Ended

A program manages an online bookstore. It contains a main menu that allows users to:

Search for books.

Add books to a shopping cart.

Checkout and make payments.

a) Draw a structure chart for this program, showing the main program and its sub-procedures. (2 marks)

b) Explain why sub-procedures are useful in this program. (2 marks)

Open Ended

A program calculates the total cost of a meal, including tax and tip. The calculation involves three steps:

Calculate tax (10% of meal cost).

Calculate tip (15% of meal cost).

Display the total cost.

a) Write pseudocode for the program, including sub-procedures for calculating tax and tip. (5 marks)

b) Explain the importance of using sub-procedures and parameters in this program. (2 marks)

Open Ended

A program for a school management system generates student grades. The steps are:

Assign grades based on scores.

Input student names and scores.

Print the grade report.

Question:

a) Put the steps in the correct order to produce a working algorithm. (2 marks)

b) Explain how incorrect ordering can affect the program's functionality. (2 marks)