Year 8 Area and Perimeter Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 8 area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · Area & PerimeterYear 8 Area and Perimeter Worksheet — Level 3 — Practice Set 4 — Answers
Write the formula, substitute, then calculate. Include units.
1.A triangle has a base of 10 mm and a perpendicular height of 15 mm. Find its area.
Answer: 75 mm2
- A = ½ × base × height = ½ × 10 × 15
- = 75 mm2
2.A triangle has a base of 14 cm and a perpendicular height of 14 cm. Find its area.
Answer: 98 cm2
- A = ½ × base × height = ½ × 14 × 14
- = 98 cm2
3.An L-shape is made from a 27 mm by 20 mm rectangle joined to a 24 mm by 8 mm rectangle. Find the total area.
Answer: 732 mm2
- Rectangle 1: 27 × 20 = 540
- Rectangle 2: 24 × 8 = 192
- Total: 540 + 192 = 732 mm2
4.An L-shape is made from a 9 mm by 10 mm rectangle joined to a 4 mm by 10 mm rectangle. Find the total area.
Answer: 130 mm2
- Rectangle 1: 9 × 10 = 90
- Rectangle 2: 4 × 10 = 40
- Total: 90 + 40 = 130 mm2
5.A triangle has a base of 18 cm and a perpendicular height of 3 cm. Find its area.
Answer: 27 cm2
- A = ½ × base × height = ½ × 18 × 3
- = 27 cm2
6.A rectangle is 4 mm long and 18 mm wide. Find its area.
Answer: 72 mm2
- A = length × width = 4 × 18
- = 72 mm2
7.A rectangle is 30 cm long and 4 cm wide. Find its area.
Answer: 120 cm2
- A = length × width = 30 × 4
- = 120 cm2
8.A triangle has a base of 9 mm and a perpendicular height of 11 mm. Find its area.
Answer: 49.5 mm2
- A = ½ × base × height = ½ × 9 × 11
- = 49.5 mm2
9.A triangle has a base of 6 cm and a perpendicular height of 11 cm. Find its area.
Answer: 33 cm2
- A = ½ × base × height = ½ × 6 × 11
- = 33 cm2
10.A rectangle is 30 mm long and 7 mm wide. Find its area.
Answer: 210 mm2
- A = length × width = 30 × 7
- = 210 mm2
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