8th Grade Area and Perimeter Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 8th Grade area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheet8th Grade · Mathematics · Area & Perimeter8th Grade Area and Perimeter Worksheet — Level 2 — Practice Set 3 — Answers
Write the formula, substitute, then calculate. Include units.
1.A rectangle is 13 cm long and 17 cm wide. Find its area.
Answer: 221 cm2
- A = length × width = 13 × 17
- = 221 cm2
2.A triangle has a base of 4 mm and a height of 5 mm. Find its area.
Answer: 10 mm2
- A = ½ × base × height = ½ × 4 × 5
- = 10 mm2
3.A rectangle is 8 m long and 13 m wide. Find its perimeter.
Answer: 42 m
- P = 2 × (8 + 13)
- = 2 × 21 = 42 m
4.A rectangle is 19 mm long and 13 mm wide. Find its area.
Answer: 247 mm2
- A = length × width = 19 × 13
- = 247 mm2
5.A rectangle is 12 m long and 15 m wide. Find its area.
Answer: 180 m2
- A = length × width = 12 × 15
- = 180 m2
6.A rectangle is 30 mm long and 5 mm wide. Find its perimeter.
Answer: 70 mm
- P = 2 × (30 + 5)
- = 2 × 35 = 70 mm
7.A triangle has a base of 20 m and a height of 4 m. Find its area.
Answer: 40 m2
- A = ½ × base × height = ½ × 20 × 4
- = 40 m2
8.A rectangle is 3 cm long and 17 cm wide. Find its perimeter.
Answer: 40 cm
- P = 2 × (3 + 17)
- = 2 × 20 = 40 cm
9.A triangle has a base of 4 m and a height of 5 m. Find its area.
Answer: 10 m2
- A = ½ × base × height = ½ × 4 × 5
- = 10 m2
10.A rectangle is 20 cm long and 2 cm wide. Find its area.
Answer: 40 cm2
- A = length × width = 20 × 2
- = 40 cm2
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