Mathematics - International - 0607 CIE

Proportion

Overview

Two quantities are in proportion when they grow or shrink together in a fixed way. Double the recipe and you double every ingredient; share a job among more workers and it takes less time each. Recognising and writing these relationships lets you predict one quantity from another with a single constant.

In this lesson you will express direct and inverse proportion in algebra, find the constant of proportionality and use it to find unknown values. You will also learn to look at a table of data and decide which model fits best, whether the link is direct, inverse, or based on a square.

Objectives

  1. Express direct and inverse proportion in algebraic terms and use this form of expression to find unknown quantities.
  2. Identify the best variation model for given data.

Lesson Note

Proportion is one of the most useful modelling ideas in all of mathematics. Cooking, currency conversion, scaling drawings, mixing chemicals and physics laws such as pressure and volume all rest on it. Once you can write a relationship as a proportion and find its constant, you can answer any what if question about it instantly.

Available on the Green Bridge App

Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.

Full lesson notes with diagrams
AI-powered learning assistant
Study offline, anytime, anywhere
Available on Android, Windows, macOS, and Linux

Lesson Evaluation

Congratulations on completing the lesson on Proportion. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.

You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.

Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.

  1. y is directly proportional to x, and y = 12 when x = 3. What is y when x = 5? A. 15 B. 20 C. 24 D. 60 Answer: B
  2. y is inversely proportional to x, and y = 6 when x = 2. What is y when x = 4? A. 2 B. 3 C. 8 D. 12 Answer: B
  3. For a direct proportion y = kx, which quantity stays constant? A. x y B. y/x C. y/x^2 D. x + y Answer: B
  4. For data with x: 1, 2, 3 and y: 3, 12, 27, which model fits? A. y = 3x B. y = 3/x C. y = 3x^2 D. y = x + 2 Answer: C
  5. Which describes inverse proportion? A. y increases as x increases at a constant rate B. y decreases as x increases, with xy constant C. y equals x squared D. y is always equal to x Answer: B

Available on the Green Bridge App

Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.

Full lesson notes with diagrams
AI-powered learning assistant
Study offline, anytime, anywhere
Available on Android, Windows, macOS, and Linux

Available on the Green Bridge App

Download the Green Bridge CBT app on your phone or computer to access full lesson notes, practice questions, and more.

Full lesson notes with diagrams
AI-powered learning assistant
Study offline, anytime, anywhere
Available on Android, Windows, macOS, and Linux

Practice Mock Questions

Want to practice mock questions on Proportion? Download the Green Bridge CBT app to access mock questions and full practice assessments for this topic.

Download The App On Google Playstore

Everything you need to excel in your exams

Green Bridge CBT Mobile App
Personalized AI Learning Chat Assistant
200,000+ Past Papers Across IGCSE, JAMB, WAEC & NECO
Over 3000 Lesson Notes
Offline Support - Learn Anytime, Anywhere
Green Bridge Timetable
Literature Summaries & Potential Questions
Track Your Performance & Progress
In-depth Explanations for Comprehensive Learning