Year 9 Area and Perimeter Worksheet — Level 3 — Practice Set 4 — 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 4 — Answers
Write the formula, substitute, then calculate. Include units.
1.An L-shape is made from a 20 mm by 10 mm rectangle joined to a 19 mm by 9 mm rectangle. Find the total area.
Answer: 371 mm2
- Rectangle 1: 20 × 10 = 200
- Rectangle 2: 19 × 9 = 171
- Total: 200 + 171 = 371 mm2
2.A rectangle is 27 mm long and 17 mm wide. Find its area.
Answer: 459 mm2
- A = length × width = 27 × 17
- = 459 mm2
3.A triangle has a base of 15 m and a perpendicular height of 3 m. Find its area.
Answer: 22.5 m2
- A = ½ × base × height = ½ × 15 × 3
- = 22.5 m2
4.An L-shape is made from a 15 mm by 3 mm rectangle joined to a 8 mm by 4 mm rectangle. Find the total area.
Answer: 77 mm2
- Rectangle 1: 15 × 3 = 45
- Rectangle 2: 8 × 4 = 32
- Total: 45 + 32 = 77 mm2
5.A triangle has a base of 10 m and a perpendicular height of 7 m. Find its area.
Answer: 35 m2
- A = ½ × base × height = ½ × 10 × 7
- = 35 m2
6.An L-shape is made from a 23 mm by 4 mm rectangle joined to a 12 mm by 8 mm rectangle. Find the total area.
Answer: 188 mm2
- Rectangle 1: 23 × 4 = 92
- Rectangle 2: 12 × 8 = 96
- Total: 92 + 96 = 188 mm2
7.A triangle has a base of 11 cm and a perpendicular height of 10 cm. Find its area.
Answer: 55 cm2
- A = ½ × base × height = ½ × 11 × 10
- = 55 cm2
8.A triangle has a base of 15 cm and a perpendicular height of 9 cm. Find its area.
Answer: 67.5 cm2
- A = ½ × base × height = ½ × 15 × 9
- = 67.5 cm2
9.A rectangle is 7 m long and 17 m wide. Find its area.
Answer: 119 m2
- A = length × width = 7 × 17
- = 119 m2
10.A rectangle is 22 mm long and 7 mm wide. Find its area.
Answer: 154 mm2
- A = length × width = 22 × 7
- = 154 mm2
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