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	Time: 12 hours Level: Introductory

	Introduction Introduction Resource This sample of S110 material is taken from Module 2, entitled Using numbers and handling data. As you read the material, bear in mind that it is taken from a work-based course, designed for those who are...

	1 Decimals 1.1 Introducing the decimal system of numbers Resource Many different systems for writing numbers have been developed over the history of humankind. 1.2 Decimal points Resource Suppose you have less than one of any particular unit: how would you represent that using the decimal system? 1.3 Marking decimals on a scale Resource Figure 2 shows a picture of a ruler. The major units are marked in centimetres (1 to 11 cm), whilst the intervals between the centimetres have each been split into ten equal, smaller units. These... 1.4 Decimal places Resource If you have less than one unit you should put a zero before the decimal point to make it easier for yourself and others to read the value (e.g. you should write 0.4 rather than just .4, as will be explained... 1.5 Rounding to decimal places Resource Sometimes the result of a calculation gives a number with lots of decimal places – far more than you need or could reliably measure. For instance, suppose a patient is required to receive 5 ml of medicine... 1.6 Multiplication and division by factors of ten Resource Moving a decimal point by one place changes the value of the number by a factor of ten. For instance, to multiply a value by ten you can just move the decimal point one place to the right: 1.7 SI units and conversions Resource The international system of units (Le Système International d'Unités: abbreviated to SI) was developed in France during the 18th century in an effort to create a unified and rational system of weights... 1.8 Adding and subtracting decimal numbers Resource By now you should be familiar with decimal numbers, the different ways in which they can be represented (written in full, or simplified by using an exponent), and understand that by moving the decimal... 1.9 Addition of decimal numbers Resource If we add 109.8 ml of one liquid to 6.5 ml of another liquid, what would be the total volume of liquid in ml? 1.10 Subtraction of decimal numbers Resource Subtraction of numbers can be used to answer questions such as ‘what's the difference between two values?’ or ‘if something has decreased by a certain amount, what's its new value?’ Subtraction can also... 1.11 Addition and subtraction in practice – fluid balance Resource A common healthcare example that uses addition and subtraction involves calculating the fluid balance of a patient.

	2 Accuracy, precision and common errors 2.1 Differences between accuracy and precision Resource Accuracy is a measure of how close a result is to the true value. Precision is a measure of how repeatable the result is. For instance, a group of three friends tried the shooting gallery at a fair and... 2.2 Checking accuracy and precision Resource The way to ensure that equipment is accurate is to use a series of known standards against which to calibrate the equipment. Calibrating should be done at least each day and sometimes more frequently (such... 2.3 Common maths problems and errors in the workplace Resource In a busy, hospital environment mistakes with medicines and other treatments can happen at any time. Some of these are caused by communication/administrative problems, whilst others are due to mathematical... 2.4 Sources of errors Resource The following is a list of common problems that can lead to medication errors. They fall into three broad categories according to where they occur in the sequence from a drug being prescribed to it being... 2.5 What is a sensible dose? Resource This will vary from drug to drug and patient to patient, but bear in mind that most drugs need to be swallowed or injected, so the manufacturer has designed the dose sizes to be as easy as possible for...

	3 Handling data 3.1 Graphs Resource Information is everywhere these days – in the form of images, written records, tables and graphs. In this part of the unit we want you to realise how useful graphs can be to analyse numerical information,... 3.2 The anatomy of a graph Resource A graph shows how two different types of data that can take on different values (known as variables) are related, or change in relation to each other; for instance, how a patient's temperature changes... 3.3 Types of graphs and their uses Resource Many different types of graphs exist, and each has something different about it that makes it useful in a unique way. Here we will be looking at just two types of graph: bar graphs and line graphs. 3.4 Bar graphs Resource The following graph (Figure 9) records how the outside diameter of a hypodermic needle is related to the needle gauge number. 3.5 Line graphs Resource To illustrate how to create and use line graphs, we will use the example of a calibration curve. 3.6 Graphs with unusual scales – graphing exponentials Resource Many natural processes involve repeated doublings or halving at regular intervals. You may have come across this already in your work, in the context of bacterial growth or radioactivity. In this section,... 3.7 Descriptive statistics Resource The average of a group of numbers (which is sometimes called the ‘mean’) represents the balancing point or middle of the data. It is found by adding together all of the individual data values and dividing... 3.8 Descriptive statistics Resource Even if we know the maximum and minimum and middle values in a group of numbers, we still don't have a clear idea about the distribution of values within that range: are most of the values all bunched...

	References and Acknowledgements Acknowledgements Resource

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