Year 7 Angles in Polygons Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 7 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 7 · Mathematics · AnglesYear 7 Angles in Polygons Worksheet — Level 2 — Practice Set 3 — Answers
Interior angle sum = (n − 2) × 180°. The exterior angles of any convex polygon add to 360°.
1.Find the sum of the interior angles of a pentagon.
Answer: 540°
- Angle sum = (n − 2) × 180°
- (5 − 2) × 180° = 540°
2.Find the size of each interior angle of a regular 18-sided polygon.
Answer: 160°
- Angle sum = (18 − 2) × 180° = 2,880°
- 2,880° ÷ 18 = 160°
3.Find the size of each exterior angle of a regular 36-sided polygon.
Answer: 10°
- Exterior angles add to 360°
- 360° ÷ 36 = 10°
4.Each exterior angle of a regular polygon is 45°. How many sides does it have?
Answer: 8
- Exterior angles add to 360°
- 360 ÷ 45 = 8 sides
5.Find the sum of the interior angles of a heptagon.
Answer: 900°
- Angle sum = (n − 2) × 180°
- (7 − 2) × 180° = 900°
6.Find the size of each interior angle of a regular pentagon.
Answer: 108°
- Angle sum = (5 − 2) × 180° = 540°
- 540° ÷ 5 = 108°
7.Find the size of each exterior angle of a regular 30-sided polygon.
Answer: 12°
- Exterior angles add to 360°
- 360° ÷ 30 = 12°
8.Each exterior angle of a regular polygon is 24°. How many sides does it have?
Answer: 15
- Exterior angles add to 360°
- 360 ÷ 24 = 15 sides
9.Find the sum of the interior angles of a quadrilateral.
Answer: 360°
- Angle sum = (n − 2) × 180°
- (4 − 2) × 180° = 360°
10.Find the size of each interior angle of a regular 30-sided polygon.
Answer: 168°
- Angle sum = (30 − 2) × 180° = 5,040°
- 5,040° ÷ 30 = 168°
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