Year 8 Area and Perimeter Worksheet — Level 2 — Practice Set 3 — 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 2 — Practice Set 3 — Answers
Write the formula, substitute, then calculate. Include units.
1.A triangle has a base of 11 mm and a perpendicular height of 8 mm. Find its area.
Answer: 44 mm2
- A = ½ × base × height = ½ × 11 × 8
- = 44 mm2
2.A rectangle is 21 cm long and 3 cm wide. Find its perimeter.
Answer: 48 cm
- P = 2 × (21 + 3)
- = 2 × 24 = 48 cm
3.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
4.A rectangle is 24 mm long and 13 mm wide. Find its perimeter.
Answer: 74 mm
- P = 2 × (24 + 13)
- = 2 × 37 = 74 mm
5.A rectangle is 14 mm long and 18 mm wide. Find its area.
Answer: 252 mm2
- A = length × width = 14 × 18
- = 252 mm2
6.A triangle has a base of 17 cm and a perpendicular height of 9 cm. Find its area.
Answer: 76.5 cm2
- A = ½ × base × height = ½ × 17 × 9
- = 76.5 cm2
7.A rectangle is 4 m long and 17 m wide. Find its perimeter.
Answer: 42 m
- P = 2 × (4 + 17)
- = 2 × 21 = 42 m
8.A rectangle is 12 cm long and 15 cm wide. Find its perimeter.
Answer: 54 cm
- P = 2 × (12 + 15)
- = 2 × 27 = 54 cm
9.A rectangle is 19 mm long and 15 mm wide. Find its perimeter.
Answer: 68 mm
- P = 2 × (19 + 15)
- = 2 × 34 = 68 mm
10.A rectangle is 16 m long and 8 m wide. Find its perimeter.
Answer: 48 m
- P = 2 × (16 + 8)
- = 2 × 24 = 48 m
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