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Primary 6 Maths: Circumference and Area of a Circle — Practice Paper 3 (10 Questions)
Primary 6 Maths: Circumference and Area of a Circle — Practice Paper 3 (10 Questions)
Paper 3 applies π = 3.14 in three settings: a diameter and area recovered from a circumference, a semicircle boundary that includes the diameter, and area subtraction for a ring and a circle cut from a square.
Quick answer Ten questions, about 22 minutes. Items 01 to 04 substitute into the circumference and area formulas and halve a diameter; items 05 to 07 work back from a circumference, add a diameter to an arc and cost grass; items 08 and 09 subtract areas; item 10 redoes a diameter used as a radius.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 questions |
| Suggested time | 22 minutes |
| Difficulty mix | Foundation 4 · Intermediate 3 · Challenge 2 · 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 5 cm. Find its circumference. (Take π = 3.14)
- FoundationA circle has a diameter of 14 cm. Find its circumference. (Take π = 3.14)
- FoundationA circle has a radius of 3 cm. Find its area. (Take π = 3.14)
- FoundationA circle has a diameter of 10 cm. Find its area. (Take π = 3.14)
- IntermediateA circle has a circumference of 62.8 cm. Find its diameter, radius and area. (π = 3.14)
- IntermediateA semicircle has a radius of 4 cm. Find its boundary length — the arc plus the diameter. (π = 3.14)
- IntermediateA circular garden has a diameter of 6 m. Grass costs $12 per square metre. Find the total cost. (π = 3.14)
- ChallengeA ring has an outer radius of 5 cm and an inner radius of 3 cm. Find the area of the ring. (π = 3.14)
- ChallengeThe largest circle is cut from a 10 cm square card. Find the waste area. (π = 3.14)
- Error redoA student finds the area of a circle with diameter 8 cm as “3.14 × 8 = 25.12 cm²”. What is the correct area?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | 31.4 cm | Circumference = 2 × 3.14 × 5 = 31.4 cm. |
| 2 | 43.96 cm | With a diameter just multiply: 3.14 × 14 = 43.96 cm. |
| 3 | 28.26 cm² | Area = 3.14 × 3 × 3 = 28.26 cm²; the radius is squared, not doubled. |
| 4 | 78.5 cm² | Radius 10 ÷ 2 = 5 cm, so the area is 3.14 × 25 = 78.5 cm². |
| 5 | Diameter 20 cm, radius 10 cm, area 314 cm² | Diameter = 62.8 ÷ 3.14 = 20 cm, radius 10 cm, area 3.14 × 100 = 314 cm². |
| 6 | 20.56 cm | The arc is half a circumference, 3.14 × 4 = 12.56 cm, plus the diameter 8 cm, so 20.56 cm in all. |
| 7 | Area 28.26 m², total $339.12 | Radius 3 m gives an area of 28.26 m², and 28.26 × 12 = $339.12. |
| 8 | 50.24 cm² | The outer circle is 78.5 cm² and the inner one 28.26 cm², so the ring is 50.24 cm². |
| 9 | 21.5 cm² | The largest circle has diameter 10 cm, so radius 5 cm and area 78.5 cm²; the waste is 100 − 78.5 = 21.5 cm². |
| 10 | The correct area is 50.24 cm²; the diameter was used as the radius | 25.12 is the circumference; the radius is 4 cm, so the area is 3.14 × 16 = 50.24 cm². |
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.
