9th Grade Area and Perimeter Worksheet — Level 2 — Answers
Answer sheet with worked solutions for the 9th Grade area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheet9th Grade · Mathematics · Area & Perimeter9th Grade Area and Perimeter Worksheet — Level 2 — Answers
Write the formula, substitute, then calculate. Include units.
1.A triangle has a base of 12 mm and a height of 14 mm. Find its area.
Answer: 84 mm2
- A = ½ × base × height = ½ × 12 × 14
- = 84 mm2
2.A rectangle is 23 mm long and 15 mm wide. Find its perimeter.
Answer: 76 mm
- P = 2 × (23 + 15)
- = 2 × 38 = 76 mm
3.A triangle has a base of 12 cm and a height of 4 cm. Find its area.
Answer: 24 cm2
- A = ½ × base × height = ½ × 12 × 4
- = 24 cm2
4.A rectangle is 12 mm long and 12 mm wide. Find its area.
Answer: 144 mm2
- A = length × width = 12 × 12
- = 144 mm2
5.A rectangle is 5 m long and 4 m wide. Find its perimeter.
Answer: 18 m
- P = 2 × (5 + 4)
- = 2 × 9 = 18 m
6.A rectangle is 4 m long and 19 m wide. Find its perimeter.
Answer: 46 m
- P = 2 × (4 + 19)
- = 2 × 23 = 46 m
7.A rectangle is 2 cm long and 10 cm wide. Find its area.
Answer: 20 cm2
- A = length × width = 2 × 10
- = 20 cm2
8.A rectangle is 24 mm long and 10 mm wide. Find its area.
Answer: 240 mm2
- A = length × width = 24 × 10
- = 240 mm2
9.A rectangle is 27 m long and 7 m wide. Find its area.
Answer: 189 m2
- A = length × width = 27 × 7
- = 189 m2
10.A rectangle is 11 mm long and 10 mm wide. Find its perimeter.
Answer: 42 mm
- P = 2 × (11 + 10)
- = 2 × 21 = 42 mm
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