The first alternative measure of dispersion we shall discuss is the interquartile range: this is the difference between summary measures known as the lower and upper quartiles. The quartiles are simple in concept: if the median is regarded as the middle data point, so that it splits the data in half, the quartiles similarly split the data into quarters. This is, of course, an over-simplification. With an even number of data points, the median is defined to be the average of the middle two: de
Author(s): The Open University

Figure 20 shows a histogram of waiting times, varying from about 40 minutes to about 110 minutes.

Author(s): The Open University

Figure 19 shows a histogram of chest measurements (in inches) of a sample of 5732 Scottish soldiers.

Author(s): The Open University

## Question 1

Find the volumes of these objects.

Author(s): The Open University

## Question 1

Find the area of a circle of (a) radius 8 cm, and (b) radius 15 m.

• (a)

Author(s): The Open University

There are two very famous formulas for circles:

circumference of a circle = Author(s): The Open University

You may like to add the area formulas in this section to your notes for future reference.

The simplest areas to find are those of rectangles. The area of a rectangle is its length multiplied by its breadth. Sometimes the dimensions of a rectangle are referred to as the base and the height, instead of the length and the breadth. The area is then expressed as the base multiplied by the height.

Two shapes are said to be similar if they are the same shape but not necessarily the same size. In other words, one may be an enlargement of the other. They may also have different orientations, as in the drawing below.

We have seen that human-induced climate change poses a challenge for people who live on islands. Such changing patterns and extremes of climate also put pressure on the other living things that are part of the make-up of island territories. However, long before human beings became aware that they could transform the flows that constitute climate, they and other species were already taking advantage of these same flows to help create the very territories that are now under threat. But have the
Author(s): The Open University

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Author(s): The Open University

Several attempts have been made to form a united front of developing countries to negotiate a better deal at the WTO. They have met with little success because there are substantial conflicts of interest between them, for example between agricultural importers and exporters, and between small countries and those larger developing countries that have been able individually to use the lure of opening their markets to get a better deal from developed countries. Conflicts of interest arise too be
Author(s): The Open University

In this unit you will find frequent references both to the wavelength of light and the frequency of light. It is important to be able to work with both, and convert from one to the other. In the context of optical-fibre communication, the light radiation we are concerned with is usually in the infrared region of the spectrum.

To identify the position in the electromagnetic spectrum it is usual to refer to the wavelength of light, rather than its frequency. Thus I will refer to the ‘13
Author(s): The Open University

Using optical fibres, very high data rates (gigabits per second and higher) can be transmitted over long distances (tens of kilometres) without amplifiers or regenerators. As a consequence, optical fibre has completely superseded copper wires as the primary medium for cabled transmission over long distances. Until recently, however, optical fibre has been used less in LANs, where twisted-pair copper cable has been dominant. Similarly, fibre has been slow to penetrate the access network, from
Author(s): The Open University

Now Ned's got three things. He's got the money that is presumably ‘good’. He's got his defence policy, which he thinks is ‘good’. Ros then introduces the well-being of the community. They are all ‘goods’ but each pulls in a different direction. Any judgement that Ned makes has to be based on an aggregation of these things. But, of course, these are quite different kinds of things, they are incommensurate, so adding up these things is not a straightforward proposition. Ros is hopin
Author(s): The Open University

Thought and Experience
This album contains fascinating and engrossing interviews with several leading philosophers concerning, primarily, the exploration of four topics: emotion; thought and language; imagination and creativity; consciousness. The interviews contain lively debates from differing philosophical viewpoints, discussions about theoretical thought experiments and the examination of theories developed by philosophers such as Aristotle, Decartes, Galileo, and Hume as well as predictions regarding the future
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Voice-leading analysis of music 2: the middleground
This free course, Voice-leading analysis of music 2: the middleground, continues our examination of 'voice-leading' or 'Schenkerian' analysis, perhaps the most widely used and discussed method of analysing tonal music. In this course, this method is explained through the analysis of piano sonatas by Mozart. The course is the second in the AA314 series of three courses on this form of harmonic analysis, and concentrates on the 'middleground level' of voice leading. As you work through this course
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Form and uses of language
In this free course, Form and uses of language, we will consider how language can be used in different ways for different purposes. To do this we will use the theme of memorial and commemoration. In the first section we briefly discuss the life of the poet Siegfried Sassoon before examining both his poetry and his prose. Through this we will see how Sassoon conveys meaning in different ways for different audiences using different forms. Following this we discuss more generally how different mean
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This course focuses on a detailed investigation into the archaelogy and history of a Roman North African city. You will watch the video sequence ‘Exploring Thugga’ and undertake activities identifying Roman and indigenous elements in the city. You then investigate Roman and indigenous cultural elements in the archaeology of Africa; here you will watch two brief video sequences on mosaics, continue your study of the ‘Exploring Thugga’ video, and view ‘Culture and identity in the hous
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This course will concentrate on one of the most common forms of art history writing – a biographical monograph about a single artist's life and work. You will be focusing on the way that one author, Helen Langdon, has used biography in her book about one artist, Caravaggio. In order to get the most out of studying this course you will need access to a copy of this book (ISBN 071266582x)

You will look in detail at the methods she has used to approach her subject and the different kinds
Author(s): The Open University

So let us turn first of all to the visual arts, and see how one artist, Stanley Spencer, created a memorial to those who died in the First World War. Spencer was profoundly affected by his experience of the war, and decorated the walls of a chapel especially designed to display his work.

First of all, it will help to have a few biographical details. This is not because you could not understand his painting without knowing about him: you could certainly pick up a lot of information about
Author(s): The Open University