8th Grade Area and Perimeter Worksheet — Level 3 — 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 3 — Practice Set 3 — Answers
Write the formula, substitute, then calculate. Include units.
1.An L-shape is made from a 14 mm by 13 mm rectangle joined to a 3 mm by 14 mm rectangle. Find the total area.
Answer: 224 mm2
- Rectangle 1: 14 × 13 = 182
- Rectangle 2: 3 × 14 = 42
- Total: 182 + 42 = 224 mm2
2.A rectangle is 23 cm long and 7 cm wide. Find its area.
Answer: 161 cm2
- A = length × width = 23 × 7
- = 161 cm2
3.A rectangle is 11 m long and 16 m wide. Find its area.
Answer: 176 m2
- A = length × width = 11 × 16
- = 176 m2
4.A rectangle is 20 mm long and 12 mm wide. Find its area.
Answer: 240 mm2
- A = length × width = 20 × 12
- = 240 mm2
5.An L-shape is made from a 17 m by 17 m rectangle joined to a 4 m by 7 m rectangle. Find the total area.
Answer: 317 m2
- Rectangle 1: 17 × 17 = 289
- Rectangle 2: 4 × 7 = 28
- Total: 289 + 28 = 317 m2
6.A rectangle is 8 m long and 3 m wide. Find its area.
Answer: 24 m2
- A = length × width = 8 × 3
- = 24 m2
7.An L-shape is made from a 30 mm by 2 mm rectangle joined to a 28 mm by 6 mm rectangle. Find the total area.
Answer: 228 mm2
- Rectangle 1: 30 × 2 = 60
- Rectangle 2: 28 × 6 = 168
- Total: 60 + 168 = 228 mm2
8.An L-shape is made from a 9 mm by 10 mm rectangle joined to a 3 mm by 9 mm rectangle. Find the total area.
Answer: 117 mm2
- Rectangle 1: 9 × 10 = 90
- Rectangle 2: 3 × 9 = 27
- Total: 90 + 27 = 117 mm2
9.An L-shape is made from a 8 mm by 2 mm rectangle joined to a 7 mm by 2 mm rectangle. Find the total area.
Answer: 30 mm2
- Rectangle 1: 8 × 2 = 16
- Rectangle 2: 7 × 2 = 14
- Total: 16 + 14 = 30 mm2
10.A triangle has a base of 15 m and a height of 12 m. Find its area.
Answer: 90 m2
- A = ½ × base × height = ½ × 15 × 12
- = 90 m2
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