Covers Lessons 8–14: Composite shapes, volume, surface area, angles on lines and in triangles.
Question 9 3 marks
A rectangular prism has length 8 cm, width 5 cm and height 3 cm.
(a) Find its volume. 1 mark
(b) Find its surface area. 2 marks
(a) V = 8 × 5 × 3 = 120 cm³ [1]
(b) SA = 2(40 + 24 + 15) = 2 × 79 = 158 cm² [2]
Question 10 3 marks
(a) Find angle $x$ if it sits on a straight line with a 48° angle. 1 mark
(b) Three angles meet at a point: 90°, 110° and $y$. Find $y$. 1 mark
(c) Two angles in a triangle are 55° and 65°. Find the third angle. 1 mark
(a) x = 180 - 48 = 132° [1]
(b) y = 360 - 200 = 160° [1]
(c) 180 - 120 = 60° [1]
Question 11 4 marks
An L-shaped room can be split into two rectangles: 10 m × 4 m and 6 m × 3 m.
(a) Find the total floor area. 2 marks
(b) Find the perimeter of the outer boundary. 2 marks
(a) Area = 40 + 18 = 58 m² [2]
(b) Outer dimensions: 10 m × 7 m. P = 2(10 + 7) = 34 m [2]