9th Grade Area and Perimeter Worksheet — Level 2 — Practice Set 4 — 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 — Practice Set 4 — Answers
Write the formula, substitute, then calculate. Include units.
1.A triangle has a base of 6 mm and a height of 4 mm. Find its area.
Answer: 12 mm2
- A = ½ × base × height = ½ × 6 × 4
- = 12 mm2
2.A triangle has a base of 18 m and a height of 9 m. Find its area.
Answer: 81 m2
- A = ½ × base × height = ½ × 18 × 9
- = 81 m2
3.A rectangle is 29 cm long and 11 cm wide. Find its area.
Answer: 319 cm2
- A = length × width = 29 × 11
- = 319 cm2
4.A triangle has a base of 15 mm and a height of 3 mm. Find its area.
Answer: 22.5 mm2
- A = ½ × base × height = ½ × 15 × 3
- = 22.5 mm2
5.A rectangle is 3 m long and 8 m wide. Find its area.
Answer: 24 m2
- A = length × width = 3 × 8
- = 24 m2
6.A rectangle is 22 mm long and 11 mm wide. Find its perimeter.
Answer: 66 mm
- P = 2 × (22 + 11)
- = 2 × 33 = 66 mm
7.A rectangle is 17 cm long and 8 cm wide. Find its area.
Answer: 136 cm2
- A = length × width = 17 × 8
- = 136 cm2
8.A rectangle is 25 cm long and 11 cm wide. Find its area.
Answer: 275 cm2
- A = length × width = 25 × 11
- = 275 cm2
9.A rectangle is 24 mm long and 18 mm wide. Find its perimeter.
Answer: 84 mm
- P = 2 × (24 + 18)
- = 2 × 42 = 84 mm
10.A rectangle is 18 mm long and 11 mm wide. Find its perimeter.
Answer: 58 mm
- P = 2 × (18 + 11)
- = 2 × 29 = 58 mm
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