Language, notation and formulas
Language, notation and formulas

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

Language, notation and formulas

3.2.1 Try some yourself

Activity 13

You are planning to paint three rooms with total wall areas of 56, 38 and 40 square metres, using paint that comes in tins which claim to cover 15 square metres per tin. How many tins will you need for each room? And how many in total?


For the first room, with a wall area of 56 square metres,

For the second room, with a wall area of 38 square metres,

For the third room, with a wall area of 40 square metres,

The total number of tins required will depend on whether you are planning to paint all the rooms in the same colour or not. If you are, the number of tins required will be

so you will need to buy 9 tins. If all the rooms are to be different colours, you will need to buy 4 tins for the first room, 3 for the second and 3 for the third – a total of 10 tins.


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