Let's solve the worksheet step by step. The goal is to
match each description (number of faces, edges, and corners) with the correct 3D shape from the options provided.
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🔍 Key Definitions:
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Face: A flat surface of a 3D shape.
-
Edge: A line segment where two faces meet.
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Corner (Vertex): A point where edges meet.
We’ll go through each question one by one.
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1) Faces: 5, Edges: 8, Corners: 5
Look at the options:
- a) Cube → 6 faces, 12 edges, 8 corners
✘
- b) Cone → 2 faces (1 curved, 1 base), 1 edge, 1 corner
✘
- c) Square pyramid → 5 faces (4 triangular + 1 square base), 8 edges, 5 corners
✔
✔ Answer: c)
> ✔️ A square pyramid has:
> - 5 faces (1 square base + 4 triangles),
> - 8 edges (4 around base, 4 from apex),
> - 5 vertices (4 base corners + 1 apex).
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2) Faces: 6, Edges: 12, Corners: 8
Options:
- a) Triangular pyramid (tetrahedron) → 4 faces, 6 edges, 4 corners
✘
- b) Rectangular prism (cuboid) → 6 faces, 12 edges, 8 corners
✔
- c) Sphere → 0 faces, 0 edges, 0 corners
✘
✔ Answer: b)
> ✔️ A rectangular prism (like a box) has:
> - 6 rectangular faces,
> - 12 edges,
> - 8 corners.
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3) Faces: 4, Edges: 6, Corners: 4
Options:
- a) Triangular prism → 5 faces, 9 edges, 6 corners
✘
- b) Cube → 6 faces, 12 edges, 8 corners
✘
- c) Tetrahedron (triangular pyramid) → 4 triangular faces, 6 edges, 4 corners
✔
✔ Answer: c)
> ✔️ A tetrahedron is a pyramid with a triangular base and 3 triangular sides — total 4 faces.
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4) Faces: 5, Edges: 9, Corners: 6
Options:
- a) Cylinder → 3 faces (2 circular bases + 1 curved surface), 2 edges (circular), 0 corners
✘
- b) Triangular prism → 5 faces (2 triangular bases + 3 rectangles), 9 edges, 6 corners
✔
- c) Cube → 6 faces, 12 edges, 8 corners
✘
✔ Answer: b)
> ✔️ Triangular prism:
> - 2 triangular bases → 2 faces,
> - 3 rectangular sides → 3 faces → total 5 faces,
> - Each triangle has 3 edges, but shared → 3 + 3 + 3 = 9 edges,
> - 6 vertices (3 on top, 3 on bottom).
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5) Faces: 6, Edges: 12, Corners: 8
This is the same as Question 2!
Options:
- a) Cube → 6 faces, 12 edges, 8 corners
✔
- b) Cone → 2 faces, 1 edge, 1 corner
✘
- c) Tetrahedron → 4 faces, 6 edges, 4 corners
✘
✔ Answer: a)
> ✔️ Cube has:
> - 6 square faces,
> - 12 edges,
> - 8 corners.
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✔ Final Answers:
| Question | Correct Option |
|--------|----------------|
| 1 | c |
| 2 | b |
| 3 | c |
| 4 | b |
| 5 | a |
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📝 Summary:
- Use known properties of common 3D shapes.
- Count carefully:
faces,
edges,
vertices.
- Remember:
Cone and cylinder have curved surfaces and are not polyhedra (so they don’t follow Euler’s formula in the same way).
-
Pyramids and
prisms are key here.
Let me know if you'd like a printable version or explanation with diagrams!
Parent Tip: Review the logic above to help your child master the concept of geometry worksheet 3rd graders.