10. The diagram shows a triangular prism, where the right-angled triangle ABC is the cross-section and the square BCED is the slanted face.
(i) If the area of the triangle is 30 x2 and the length of the base of the
triangle [AB] is 12 x , calculate the area of the blue square in terms of x . (ii) If the volume of the prism equals 390 units3
, calculate the value of x .
11. A cylindrical container that holds three tennis balls has a height of 18 centimetres and a diameter of 6 centimetres. Each ball in the container has a radius of 3 centimetres.
(i) Calculate the volume of the cylindrical container in terms of π . (ii) Calculate the volume of the three balls in the container in terms of π . (iii) What percentage of the container is not taken up by the three balls?
The manufacturer is thinking of switching the container to a square-based cuboid shape, as she believes there will be less empty space inside this shape.
The cuboid container has the following dimensions, height = 18 cm, length of square base 6 cm.
(iv) Is the manufacturer’s assumption correct? Show all work and justify your answer.
C 30x2 A 12x B
E D
Now that you have completed the unit, revisit the
Something to think about …
question posed at the start of this unit.
Now try questions 1 and 5 from the Linking Thinking section on pages 359–360