## Activity 5

Convert each of the following fraction ratios to decimal ratios.

• (a) Author(s): The Open University

Although ratios are often given as fractions, they can also be expressed as decimals. You need to deal with a mixture of fractions and decimals, and to compare ratios given in either form, so you need to be able to convert between the two forms.

## Example 4

The ratio of the circ
Author(s): The Open University

To make short crust pastry, one recipe book says ‘use one part of fat to two parts of flour’; another recipe says ‘use fat and flour in the ratio of one to two’; and yet another says ‘use half as much fat as flour’. These are different ways of expressing the same ratio. Ratios are often expressed as fractions. So in this case:

Author(s): The Open University

After studying this course, you should be able to:

• work with simple ratios

• convert between fractions, decimals and percentages

• explain the meaning of ratio, proportion and percentage

• find percentages of different quantities

• calculate percentage increases and decreases.

Author(s): The Open University

The content acknowledged below is Proprietary (see and conditions made available under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence) and used under licence.

Course image: rod
Author(s): The Open University

Ahmed, A. (1987) Better Mathematics, London, HMSO.
DfEE (2001) Key Stage 3 National Strategy: Framework for Teaching Mathematics: Years 7, 8 and 9, London, DfEE.
NCTM (1989) Curriculum and Evaluation Standards for School Mathematics Reston VA, National Council of Teachers of Mathematics.

Author(s): The Open University

## Study another free course

There are more than 800 courses on OpenLearn for you t
Author(s): The Open University

In this course you have been introduced to the difference between mathematical content and processes. You have worked on the do–talk–record (DTR) framework for learning mathematics.

Author(s): The Open University

Mathematical processes are different from content in that they overarch the subject and are not thought of as hierarchical. A list of processes could contain:

• problem-solving (including investigating);

• mathematical modelling;

• reasoning;

• communicating;

• making connections (including applying mathematics); and

• using tools.

Each of the six processes listed here repre
Author(s): The Open University

You will come to this course with many memories of mathematics, both as a teacher and a learner. It may help if you start by recalling memories of learning mathematics and making a record of them in your notebook.

When you work on a task, get into the habit of having your notebook to hand to record your thinking. Use the notebook in any way that helps you to think about the work you have done. Some people find it helpful to divide a page into two columns using the left-hand side to reco
Author(s): The Open University

You should not expect always to be able to read a problem and then just write down the answer. When you are faced with a written mathematical question or problem to solve, read it carefully. It is important that you get to grips with the question in two ways: first, that you absorb the information given; and second, that you find out what the question is really asking. Your solution will link the two. This method can be summarised by the following questions.

Author(s): The Open University

Environmental Ethics
To what extent does Man have a right to exploit nature in order to live? Do animals have rights? Should we modify the genes of crops if it allows us to increase production, and even alleviate poverty? This album explores the arguments for and against genetically-modified crops, hearing the views of a dairy farmer competing in the global market, a GM scientist, an activist who believes GM crops are unsustainable, and an organic cultivator. The various views reveal how the debate is made complex b
Author(s): The OpenLearn team

Understanding the environment: Learning and communication
There is increasing recognition that the reductionist mindset that is currently dominating society, rooted in unlimited economic growth unperceptive to its social and environmental impact, cannot resolve the converging environmental, social and economic crises we now face. The primary aim of this free course, Understanding the environment: Learning and communication, is to encourage the shift away from reductionist and human centred thinking towards a holistic and ecological worldview.
Author(s): Creator not set

This unit explores conceptual tools for assisting our thinking and deliberation on what matters. In Section 1, a reading by Ronald Moore introduces the notion of 'framing' nature, raising the perceived paradox of inevitably devaluing an aesthetically pleasing unframed entity. Three further readings, two from Fritjof Capra and one from Werner Ulrick (all of which are quite short and markedly reduced from their original courses), provide an understanding of systems thinking for explicitly frami
Author(s): The Open University

Biofuels
This free course, Biofuels, investigates what is meant by a biofuel and covers the advantages of using biofuels compared with fossil fuels. The different types of biofuel are explored, with particular emphasis on transport biofuels. Finally, the issue of whether biofuels are the complete answer to our future energy needs is considered. First published on Mon, 21 Mar 2016 as
Author(s): Creator not set

Surface water
Water is arguably the most important physical resource as it is the one that is essential to human survival. Understanding the global water cycle and how we use water is essential to planning a sustainable source of water for the future. In the UK there are areas where water supplies are limited, as shown by recent droughts. Globally, there are many areas that do not have enough water to support the current population adequately. Decisions will have to be made on the best way to use water in a w
Author(s): Creator not set

Energy resources: Tidal energy
The rise and fall of ocean tides result from the combined gravitational pull on water by the Moon and, to a lesser extent, the Sun, which exerts a force on water directed towards the two astronomical bodies. These gravitational effects combine with centrifugal forces that result from the Earth and the Moon orbiting each other. All of which makes tidal change a complex process. Energy resources: Tidal energy, is a free course that considers the power of the ocean tides as a potential source of us
Author(s): Creator not set

Understanding the environment: A systems approach
There is increasing recognition that the reductionist mindset that is currently dominating society, rooted in unlimited economic growth unperceptive to its social and environmental impact, cannot resolve the converging environmental, social and economic crises we now face. Understanding the environment: A systems approach, is a free course whose primary aim is to encourage the shift away from reductionist and human centred thinking towards a holistic and ecological worldview. It promotes the shi
Author(s): Creator not set

Understanding the environment: Thinking styles and models
There is increasing recognition that the reductionist mindset that is currently dominating society, rooted in unlimited economic growth unperceptive to its social and environmental impact, cannot resolve the converging environmental, social and economic crises we now face. The primary aim of this freee course, Understanding the environment: Thinking styles and models, is to encourage the shift away from reductionist and human centred thinking towards a holistic and ecological worldview.
Author(s): Creator not set

Sustainable Scotland
Sustainable Scotland is a free course that will appeal to anyone with an interest in a sustainable future in the context of contemporary Scottish society. It will give you a broad-based introduction to a number of different aspects of sustainability that impact on Scotland and the wider world. First published on Wed, 30 Mar 2016 a
Author(s): Creator not set