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Primary 6 Maths: Circumference and Area of a Circle — Practice Paper 4 (10 Questions)
Primary 6 Maths: Circumference and Area of a Circle — Practice Paper 4 (10 Questions)
Paper 4 uses π = 3.14 throughout: circumference and area from a radius or a diameter, then a radius recovered from a circumference; the middle items cover a semicircle boundary and a ring, and the last items a path around a pool, two circles compared and an area from a circumference, before the error of using the circumference formula for area.
Quick answer Ten questions, about 20 minutes. Items 01 to 03 cover circumference from a radius, area from a diameter and fencing; items 04 to 06 cover a radius back from a circumference, a semicircle and a ring; items 07 to 09 cover a path, two circles compared and an area from a circumference; item 10 redoes using the circumference formula for area.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 questions |
| Suggested time | 20 minutes |
| Difficulty mix | Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1 |
| Chapter | Chapter: Primary 6 Maths: Circumference and Area of a Circle — Tutor Lesson Plan |
| Level | Primary 6 |
02 Questions (10 items)
- FoundationA circle has a radius of 4 cm. What is its circumference? (Take π = 3.14)
- FoundationA circle has a diameter of 14 cm. What is its area? (Take π = 3.14)
- FoundationA round flower bed has a diameter of 20 m. How much fencing goes round its edge? (Take π = 3.14)
- IntermediateA circle has a circumference of 31.4 cm. What are its radius and area? (Take π = 3.14)
- IntermediateA semicircle has a radius of 6 cm. What are its area and its perimeter? (Take π = 3.14)
- IntermediateA ring has an outer radius of 8 cm and an inner radius of 5 cm. What is its area? (Take π = 3.14)
- ChallengeA round pool has a diameter of 8 m with a 1 m wide path around it. What is the area of the path? (Take π = 3.14)
- ChallengeTwo circles have radii of 3 cm and 6 cm. How many times the smaller area is the larger, and what is the difference? (Take π = 3.14)
- ChallengeA circle has a circumference of 37.68 cm. What is its area? (Take π = 3.14)
- Error redoA circle has a radius of 5 cm and a student gives its area as 31.4 cm². What is the correct area and what went wrong? (Take π = 3.14)
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 25.12 cm | Circumference = 2πr = 2 × 3.14 × 4 = 25.12 cm. |
| 2 | 153.86 cm² | The radius is 7 cm, so the area is 3.14 × 7 × 7 = 153.86 cm². |
| 3 | 62.8 m | The fence is the circumference: 3.14 × 20 = 62.8 m. |
| 4 | radius 5 cm, area 78.5 cm² | Diameter = 31.4 ÷ 3.14 = 10 cm, so the radius is 5 cm and the area is 3.14 × 25 = 78.5 cm². |
| 5 | area 56.52 cm², perimeter 30.84 cm | The area is half the full circle: 3.14 × 36 ÷ 2 = 56.52 cm². The perimeter also includes the diameter: 18.84 + 12 = 30.84 cm. |
| 6 | 122.46 cm² | Subtract the inner circle from the outer: 3.14 × (64 − 25) = 3.14 × 39 = 122.46 cm². |
| 7 | 28.26 m² | The inner radius is 4 m and the outer radius is 5 m, so 3.14 × (25 − 16) = 28.26 m². |
| 8 | 4 times, a difference of 84.78 cm² | Doubling the radius multiplies the area by 4: 113.04 cm² and 28.26 cm² differ by 84.78 cm². |
| 9 | 113.04 cm² | Diameter = 37.68 ÷ 3.14 = 12 cm, so the radius is 6 cm and the area is 3.14 × 36 = 113.04 cm². |
| 10 | 78.5 cm²; the circumference formula 2πr was used | Area = πr² = 3.14 × 25 = 78.5 cm². The 31.4 is 2 × 3.14 × 5, which is the circumference. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.
