Language, notation and formulas
Language, notation and formulas

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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.


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