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Primary 5 Maths: 3-D Shapes and Nets — Practice Paper 3 (10 Questions)
Primary 5 Maths: 3-D Shapes and Nets — Practice Paper 3 (10 Questions)
Paper 3 works backwards and cuts: finding the base from edge or vertex counts, what happens when a cube corner is sliced off, the perimeter of a net and the total area of six faces, all checked with Euler formula.
Quick answer 10 questions, about 20 minutes. Items 01 to 03 find the base from edge and vertex counts, item 04 is the tetrahedron, item 05 tests slicing, items 06 and 07 measure a net, items 08 and 09 identify a solid from its faces, item 10 is the usual prism-pyramid mix-up.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 questions |
| Suggested time | 20 minutes |
| Difficulty mix | Foundation 4 · Intermediate 3 · Challenge 2 · Error redo 1 |
| Chapter | Chapter: Primary 5 Maths: 3-D Shapes and Nets — Tutor Lesson Plan |
| Level | Primary 5 |
02 Questions (10 items)
- FoundationA prism has 18 edges. What polygon is its base?
- FoundationA pyramid has 10 vertices. What polygon is its base?
- FoundationA prism has 14 vertices. What polygon is its base, and how many edges has it?
- FoundationHow many faces, edges and vertices has a triangular pyramid (tetrahedron)?
- IntermediateOne corner of a cube is sliced off, removing a single vertex. How many faces, edges and vertices has the remaining solid?
- IntermediateA net is made of six squares of side 3 cm: four in a row, one above the second square and one below the third. What is its perimeter?
- IntermediateA cuboid measures 4 cm by 3 cm by 2 cm. What is the total area of the six faces in its net?
- ChallengeThe net of a prism has two ten-sided polygons and ten rectangles. What solid is it, and how many edges has it?
- ChallengeA solid has 8 faces, 18 edges and 12 vertices. Is it a prism or a pyramid, and what polygon is its base?
- Error redoA pyramid has 6 faces. How many edges has it? (common slip: treating it as a four-sided prism and answering 12)
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | A hexagon (hexagonal prism) | A prism has 3 edges per base side, so 18 ÷ 3 = 6 sides; the 8 faces and 12 vertices confirm it. |
| 2 | A nine-sided polygon (nine-sided pyramid) | A pyramid has one vertex per base side plus the apex, so 10 − 1 = 9 sides and 9 × 2 = 18 edges. |
| 3 | A heptagon, 21 edges | A prism has twice as many vertices as base sides, so 14 ÷ 2 = 7 sides and 7 × 3 = 21 edges. |
| 4 | 4 faces, 6 edges, 4 vertices | One triangular base plus three triangular sides; 4 + 4 − 6 = 2 confirms Euler formula. |
| 5 | 7 faces, 15 edges, 10 vertices | The cut adds a triangular face, shortens three edges and adds three new ones: 6 + 1, 12 + 3, 8 − 1 + 3, and 7 + 10 − 15 = 2 holds. |
| 6 | 42 cm | Six squares give 24 unit edges; the five joins hide 10 of them, leaving 14 outside, and 14 × 3 = 42 cm. |
| 7 | 52 cm² | Three pairs of faces: (4×3 + 4×2 + 3×2) × 2 = (12 + 8 + 6) × 2 = 52. |
| 8 | A ten-sided prism, 30 edges | The rectangles match the base sides, so ten rectangles mean a ten-sided base; edges are 10 × 3 = 30, with 12 faces and 20 vertices and 12 + 20 − 30 = 2. |
| 9 | A prism (hexagonal), with a hexagonal base | For a prism faces are base sides + 2, so 8 − 2 = 6 sides; 6 × 3 = 18 edges and 6 × 2 = 12 vertices agree, while a pyramid would have base sides + 1 faces. |
| 10 | 10 edges | A pyramid has base sides + 1 faces, so 6 − 1 = 5 base sides and 5 × 2 = 10 edges; 6 + 6 − 10 = 2 checks it. |
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.
