8th Grade Area and Perimeter Worksheet — Level 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 3 — Answers
Write the formula, substitute, then calculate. Include units.
1.An L-shape is made from a 19 m by 14 m rectangle joined to a 9 m by 12 m rectangle. Find the total area.
Answer: 374 m2
- Rectangle 1: 19 × 14 = 266
- Rectangle 2: 9 × 12 = 108
- Total: 266 + 108 = 374 m2
2.A rectangle is 13 mm long and 17 mm wide. Find its area.
Answer: 221 mm2
- A = length × width = 13 × 17
- = 221 mm2
3.A triangle has a base of 7 m and a height of 13 m. Find its area.
Answer: 45.5 m2
- A = ½ × base × height = ½ × 7 × 13
- = 45.5 m2
4.A triangle has a base of 18 mm and a height of 11 mm. Find its area.
Answer: 99 mm2
- A = ½ × base × height = ½ × 18 × 11
- = 99 mm2
5.A rectangle is 11 m long and 10 m wide. Find its area.
Answer: 110 m2
- A = length × width = 11 × 10
- = 110 m2
6.A rectangle is 14 cm long and 15 cm wide. Find its area.
Answer: 210 cm2
- A = length × width = 14 × 15
- = 210 cm2
7.A rectangle is 9 cm long and 14 cm wide. Find its area.
Answer: 126 cm2
- A = length × width = 9 × 14
- = 126 cm2
8.A triangle has a base of 17 cm and a height of 3 cm. Find its area.
Answer: 25.5 cm2
- A = ½ × base × height = ½ × 17 × 3
- = 25.5 cm2
9.A rectangle is 18 cm long and 16 cm wide. Find its area.
Answer: 288 cm2
- A = length × width = 18 × 16
- = 288 cm2
10.A triangle has a base of 14 m and a height of 13 m. Find its area.
Answer: 91 m2
- A = ½ × base × height = ½ × 14 × 13
- = 91 m2
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