Year 9 Area and Perimeter Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 9 area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · Area & PerimeterYear 9 Area and Perimeter Worksheet — Level 3 — Answers
Write the formula, substitute, then calculate. Include units.
1.A rectangle is 22 mm long and 5 mm wide. Find its area.
Answer: 110 mm2
- A = length × width = 22 × 5
- = 110 mm2
2.A triangle has a base of 6 cm and a perpendicular height of 10 cm. Find its area.
Answer: 30 cm2
- A = ½ × base × height = ½ × 6 × 10
- = 30 cm2
3.A rectangle is 10 mm long and 8 mm wide. Find its area.
Answer: 80 mm2
- A = length × width = 10 × 8
- = 80 mm2
4.A triangle has a base of 5 m and a perpendicular height of 8 m. Find its area.
Answer: 20 m2
- A = ½ × base × height = ½ × 5 × 8
- = 20 m2
5.A rectangle is 4 m long and 4 m wide. Find its area.
Answer: 16 m2
- A = length × width = 4 × 4
- = 16 m2
6.A triangle has a base of 11 mm and a perpendicular height of 14 mm. Find its area.
Answer: 77 mm2
- A = ½ × base × height = ½ × 11 × 14
- = 77 mm2
7.An L-shape is made from a 15 cm by 6 cm rectangle joined to a 7 cm by 7 cm rectangle. Find the total area.
Answer: 139 cm2
- Rectangle 1: 15 × 6 = 90
- Rectangle 2: 7 × 7 = 49
- Total: 90 + 49 = 139 cm2
8.An L-shape is made from a 3 cm by 6 cm rectangle joined to a 2 cm by 2 cm rectangle. Find the total area.
Answer: 22 cm2
- Rectangle 1: 3 × 6 = 18
- Rectangle 2: 2 × 2 = 4
- Total: 18 + 4 = 22 cm2
9.An L-shape is made from a 13 m by 3 m rectangle joined to a 4 m by 6 m rectangle. Find the total area.
Answer: 63 m2
- Rectangle 1: 13 × 3 = 39
- Rectangle 2: 4 × 6 = 24
- Total: 39 + 24 = 63 m2
10.A rectangle is 30 mm long and 15 mm wide. Find its area.
Answer: 450 mm2
- A = length × width = 30 × 15
- = 450 mm2
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