12. (i) Calculate the surface area of this cuboid. Give your answer in terms of x .
Taking it FURTHER
(ii) If x = 3, calculate: (a) the actual surface area of the cuboid (b) the volume of the cuboid.
13. Container A was fi lled with water to the the top. Then some of the water was poured into the empty Container B so that the height of the water in both containers was equal. Find the new height of the water in both containers.
x + 2 2 x + 1 5 x
40 cm ? 25 cm 30 cm Container A 25 cm
Container B 18 cm
3.4 Volume, surface area and net of a cylinder
By the end of this section you should be able to: ● recall how to calculate the volume of a cylinder
● calculate the curved surface and total surface area of a cylinder
● calculate the volume of shapes consisting of diff erent cylinders
Finding the volume of a cylinder In Linking Thinking 1 we discovered how to fi nd the volume of a cylinder. Radius (r)
Height (h)
Height (h)
Radius (r)
Volume of a cylinder = π × radius × radius × height V = πr2
h This formula appears in the formulae and tables booklet. Discuss and discover
The diagram shows a can of beans, which is in the shape of a cylinder.
(i) If you were to remove the label from the can and spread it out fl at, what shape would it be?
(ii) We already know the height of the label. Find the length of the label. Clearly outline all the steps you followed to do this.
(iii) Calculate the area of the label.
(iv) How does the area of the rectangular label relate to the curved surface area of the cylinder?
(v) Is there a relationship between the circumference of the lid of the cylinder and the length of the label?
Section A Applying our skills 67 h = 10 cm BEANS r = 5 cm