Year 9 Area and Perimeter Worksheet — Level 3 — Practice Set 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 — Practice Set 3 — Answers
Write the formula, substitute, then calculate. Include units.
1.A rectangle is 29 mm long and 3 mm wide. Find its area.
Answer: 87 mm2
- A = length × width = 29 × 3
- = 87 mm2
2.A triangle has a base of 8 mm and a perpendicular height of 12 mm. Find its area.
Answer: 48 mm2
- A = ½ × base × height = ½ × 8 × 12
- = 48 mm2
3.A rectangle is 7 cm long and 8 cm wide. Find its area.
Answer: 56 cm2
- A = length × width = 7 × 8
- = 56 cm2
4.A triangle has a base of 7 mm and a perpendicular height of 10 mm. Find its area.
Answer: 35 mm2
- A = ½ × base × height = ½ × 7 × 10
- = 35 mm2
5.A rectangle is 8 cm long and 12 cm wide. Find its area.
Answer: 96 cm2
- A = length × width = 8 × 12
- = 96 cm2
6.An L-shape is made from a 18 mm by 12 mm rectangle joined to a 6 mm by 15 mm rectangle. Find the total area.
Answer: 306 mm2
- Rectangle 1: 18 × 12 = 216
- Rectangle 2: 6 × 15 = 90
- Total: 216 + 90 = 306 mm2
7.An L-shape is made from a 23 mm by 6 mm rectangle joined to a 14 mm by 2 mm rectangle. Find the total area.
Answer: 166 mm2
- Rectangle 1: 23 × 6 = 138
- Rectangle 2: 14 × 2 = 28
- Total: 138 + 28 = 166 mm2
8.A rectangle is 30 cm long and 8 cm wide. Find its area.
Answer: 240 cm2
- A = length × width = 30 × 8
- = 240 cm2
9.An L-shape is made from a 18 cm by 5 cm rectangle joined to a 2 cm by 9 cm rectangle. Find the total area.
Answer: 108 cm2
- Rectangle 1: 18 × 5 = 90
- Rectangle 2: 2 × 9 = 18
- Total: 90 + 18 = 108 cm2
10.A triangle has a base of 13 cm and a perpendicular height of 3 cm. Find its area.
Answer: 19.5 cm2
- A = ½ × base × height = ½ × 13 × 3
- = 19.5 cm2
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