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Listed under:  Mathematics  >  Number (Mathematics)  >  Proportions  >  Ratios
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Indigo Interior

This resource is a web page containing a problem solving task that requires an understanding of Pythagoras' theorem. The task involves finding the area of shaded region with a circle with a known area. To solve the problem students need to establish a right angled triangle and apply Pythagoras' theorem. A printable resource ...

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Tuning and Ratio

This resource is a web page containing a challenging problem solving task that requires an understanding of ratios and logarithms. It explains how intervals such as an octave corresponds to a particular ratio of string lengths which produce the notes. Two types of tuning based on ratios; The Pythagorean Scale and Just Intonation ...

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Round and Round and Round

This resource is a web page containing an interactive that can be used to explore the relationships between the angles of turn that produce the same vertical and horizontal displacements. The task provides an opportunity to apply their understanding of division and recurring decimals. A 'Getting started' page, printable ...

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reSolve: Tree Biomass

In this sequence of two lessons, students investigate how many trees would be required to supply paper for their school for a year. Students use similar triangles, Pythagoras' Theorem and algebra to design and construct a Biltmore stick, used to measure the diameter and height of a tree. They measure trees, calculate their ...

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reSolve: Gradient and Tangent

This sequence of two lessons investigates gradient and angle by applying the tangent ratio to find the angles represented by a road sign or the angle of a street. In the first lesson, students research what a road grade is and determine the actual angle of a road given its grade. They then construct their own road sign ...

Online

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 ...

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reSolve: Mechanical Linkages: Similar Triangles

This sequence of lessons explores the geometry of similar triangles using two real world objects: ironing boards and pantographs. In the first lesson, students investigate different ironing board leg lengths and pivot positions using similar and congruent triangles. In the second lesson, they use their knowledge of parallelogram ...

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Mystery man Pythagoras meets his match

What do you know about Pythagoras? Join Vi Hart as she not only explains his theorem but raises some legends about his dark past! Follow Vi's timeline of famous mathematicians to find out in which century Pythagoras lived. See how Vi shows a proof of his theorem and raises what was a big dilemma for Pythagoras: the irrational ...

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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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Modelling climate changes

There is a saying: 'climate is what you expect and weather is what you get'. |Understanding climate change is very difficult for most people, especially when the weather we experience is different from the information we are given by scientists about the climate changing. The difference is that weather reflects short-term ...

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Mixing Paints

This resource is a web page containing an investigative task to explore ratios. The context of mixing paints to particular ratios of colours provides a useful task to model practical situations involving ratios. A 'Getting started' and 'Solutions' page is also available to support the task. This resource is an activity ...

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Six Notes All Nice Ratios

This resource is a web page containing a short task to explore ratio and fractions. The task is based on the Pythagoreans discovery that simple ratios of string length made nice sounds together. A 'Getting started' page, printable resource and solution is also available to support the task.This resource is an activity ...

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reSolve: Fibonacci Miles

This lesson introduces students to a trick for quick conversion between miles and kilometres using the Fibonacci sequence. Students are challenged to explain why the trick works. They investigate using their knowledge of ratio and discover that the miles/kilometres conversion rate is close to the golden ratio. The lesson ...

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Burning Down

This resource is a web page containing a challenging problem solving task that requires an understanding of rate and proportion. It can be solved in a number of ways for example graphically, using fractions or equations and all involve reasoning. A printable resource and solution is also available to support the task. This ...

Online

reSolve: Monte Carlo Simulations

This sequence of two lessons explores how statistical techniques that rely on randomly generated data can be used to solve problems. In the first lesson, students compare different methods for calculating the area of an irregular shape, using the context of oil spill maps. They are introduced to the Monte Carlo method for ...

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Catalyst: Applying trigonometry: leaning tower

The Leaning Tower of Gingin is the centrepiece of the Gravity Discovery Centre. The Catalyst team of Derek, Simon and Anja drop watermelons from the tower, to examine the rate at which they fall. They are testing Galileo's theory about falling objects. The dimensions of the tower provide an opportunity to apply some basic ...

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Stateline: Mapping farmland: using area and trigonometry

In northern Queensland's Gulf region, some farmers use GPS mapping to help manage their extensive properties. Use this clip as a context for applying your understanding of area, in particular your understanding of conversion between square kilometres and hectares. Apply trigonometry and Pythagoras' theorem.

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Laptop wrap: Talking trigonometry

In this laptop-friendly resource, students consolidate their understanding of trigonometry by investigating practical applications of the ratios, highlighting the process they used to find a solution.

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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.

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The Mathematical Toolkit

A 2D Shapes tool that can be used to create geometric objects such as quadrilaterals, circles, triangles, lines, arcs, rays, segments and vectors on a coordinate grid. Plot and label the vertices to reveal the internal angles, side lengths, area and perimeter, then manipulate the shapes on a grid to transform their shape ...