Mathematics / Year 7 / Number

Curriculum content descriptions

recognise, represent and solve problems involving ratios (AC9M7N08)

Elaborations
  • using diagrams, physical or virtual materials to represent ratios, recognising that ratios express the quantitative relationship between 2 or more groups; for example, using counters or coloured beads to show the ratios \(1:4\) and \(1:1:2\)
  • using fractions to solve ratio problems involving comparison of quantities and considering part-part and part-whole relations; for example, dividing a set into the ratio \(1:2\) by determining the number of parts as \(3\)
  • sharing quantities in a given ratio; for example, sharing an amount of money in a given ratio, such as sharing \(\$20\) in the ratio \(2:3\)
  • applying ratios to realistic and meaningful contexts; for example, mixing \(500\) millilitres of a liquid with a concentration of \(1:4\) means \(\frac15\) concentrate and \(\frac45\) water so, \(0.2\) of \(500\) millilitres is concentrate and \(0.8\) of \(500\) millilitres is water; interpreting results in context
General capabilities
  • Numeracy Numeracy
ScOT terms

Simple fractions,  Ratios

Video

Proportional reasoning video

Use this video as a springboard to explore scaling or proportional thinking, and to apply that thinking in a food context, drawing on reasoning and mathematical modelling.

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Sandcastle ratios

In this lesson students think like geotechnical engineers, exploring the properties of sand and the ways in which those properties can be used in building and construction.

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reSolve: Paint with Numbers

This sequence of three lessons explores ratios through the context of mixing paint. Students investigate how ratios express a multiplicative relationship between two measures and under what conditions the proportions remain constant when the numerical values of both quantities change. The lessons are outlined in detail ...

Video

Are plants mathematicians?

Ever noticed that plants are examples of Fibonacci numbers? Watch Vi Hart draw examples of flower petals and leaf growth that follow this pattern. See how plants seem to use Phi (.), the golden ratio. Find out how to make your own 'angle-a-tron' to create interesting petal designs. This is the second in a series of two.

Interactive

Syllabus Bites: Revisiting proportion

This is the first in a series of Syllabus Bites related to direct and indirect proportion. Students revise the concept of ratio. They create short visual explanations showing how problems can be solved.

Video

Catalyst: Take the Phi Golden challenge

The golden ratio, Phi: fact or fallacy? What about the Fibonacci sequence? We are told this ratio and its cousin Fibonacci occur everywhere in nature. Let's see which of these claims stacks up when put to the test.

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Expressing one quantity as a fraction of a second

This is a website designed for both teachers and students that addresses the expression of one quantity as a fraction of a second quantity from the Australian Curriculum for year 7 students. It contains material on using the unitary method to solve fraction problems. There are pages for both teachers and students. The student ...

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TIMES Module 17: Number and Algebra: the unitary method - teacher guide

This is an 18-page guide for teachers. This module introduces the idea of ratios and rates.

Interactive

Squirt: three containers

Examine the relationships between capacities of various containers. Look at three containers that may have different diameters, heights and shapes. Fill a container and squirt liquids between the containers to establish the proportional relationship. Work out the third 'unlinked' relationship from two known relationships. ...

Interactive

Renovate, Calculate!

A student resource that explores the use of mathematics in the trades. Highly interactive investigations into ratio, areas of special quadrilaterals and right-angled trigonometry.

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reSolve: Modelling Motion - Year 7

This sequence of seven lessons challenges students to use simple equipment to predict, observe and represent motion. They create a series of graphs to represent motion and construct instruments to measure forces in one and then two dimensions. They interpret these representations to develop concepts of force and motion. ...

Video

BTN: What is the GST?

The Goods and Services Tax (GST) is a tax placed on things people buy with money or things people do for money. Can you name some goods and services that have GST? What about some goods and services that don't have GST? Find out when and why the GST was first introduced.

Video

Comparing fuel consumption

Is it more fuel efficient to drive or fly between two places? Watch this clip and learn how to calculate the answer. What are the various factors that need to be taken into account? This video was made using the American measurement of gallons per hour, American firgures for the average number of passengers in a car and ...

Video

Maths inside bees and beehives

Bees are necessary for assisting many plants to produce the food we eat, including meat and milk. Colony collapse disorder, which describes the disappearance of beehives, could have catastrophic effects on food production. Australian scientists are applying their maths and science knowledge to build up a picture of a healthy ...

Video

How does income tax work?

Gen Fricker makes income tax interesting! Learn about income tax - what it is, how it works and when you have to pay it. Easy-peasy! Then test yourself with ASIC Moneysmart's "Things to think about" classroom exercises.

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MathXplosion, Ep 50: How to use a tetrahedron to solve the tree problem

How can you place four trees exactly the same distance apart from one other? By making a model! By using miniature trees to make a model of the problem, it becomes clear that a 2D solution is impossible. We learn how objects can help us visualise the problem situation, which in this case requires a 3D solution: a tetrahedron.

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My Five Cents: Why borrowing can cost you more

Think credit cards are basically free money? Gen Fricker will make you think again. Learn how interest rates and fees affect the money you borrow, and why they may be more expensive in the long run. Oh dear! Then test yourself with ASIC MoneySmart's "Things to think about" classroom exercises.  

Video

MathXplosion, Ep 1: Magic 9s

Follow these simple calculations to illustrate the special properties of the number 9. Pick your favourite number between 1 and 9 and multiply that number by 3. Add 3 to your answer. Multiply the result by 3. Treat your two-digit answer as two separate numbers and add them together. No matter what number you pick to start ...

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MathXplosion, Ep 40: Kaprekar's operation

Did you know that 6,174 is a very mysterious number? In 1949, the mathematician Dr Kaprekar from India devised a process now known as Kaprekar's operation. First, choose a four-digit number where the digits are all different. Then rearrange the digits to get the largest and smallest numbers these digits can make. Finally, ...

Interactive

Converting decimals to percentages

This interactive resource consists of a series of questions about converting decimals into percentages. The viewer is required to convert a decimal number into a percentage and enter the answer in a window on the screen. The answer can be checked and, if correct, the viewer moves to the next question. Help is available ...