Using numbers and handling data
Using numbers and handling data

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

Free course

Using numbers and handling data

1.3 Marking decimals on a scale

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 minor units are therefore tenths of a centimetre, commonly known as 'millimetres'. (There are 10 millimetres in 1 centimetre.) A similar type of decimal scale is used on many devices that you will work with, such as syringes, gas pressure gauges and pH meters, even though the physical quantities they measure, and therefore their units of measurement, are different.

In Figure 2 several numbers have been highlighted to allow you to relate the way a decimal number is written to the quantity that number represents. For instance, if our units of measurement are centimetres, then we can see that 0.3 cm is less than 1 cm (it is actually 3 millimetres). Similarly, 2 cm is less than 3.5 cm. However, 70 mm is less than 10.2 cm, because 70 mm means the same as 7 cm.

Figure 2
Figure 2 Units and tenths of units represented on a ruler

Now practise placing decimal values on a similar scale for yourself with practice questions 4 to 8.

Right click and open the practice questions [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] in a separate window, then you can switch easily between the course text and the questions.

S110_1

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to University-level study, we offer two introductory routes to our qualifications. You could either choose to start with an Access module, or a module which allows you to count your previous learning towards an Open University qualification. Read our guide on Where to take your learning next for more information.

Not ready for formal University study? Then browse over 1000 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus371