Primary 6 · Mathematics · 3D Solids & Nets
3D Solids & Nets questions for Primary 6 Maths
10 questions to work through online. Answer and you get the working straight away, then a score at the end. No sign-up, and you can retake it as often as you like.
- Counting faces
- Counting edges
- Counting vertices
- Nets
- Euler's relation
- Naming solids
- Properties of solids
Answers and explanations for all 10 questions
Every answer with the reasoning behind it. Worth reading after you have tried the set — or on its own, if you are a parent marking it.
How many faces does a triangular pyramid (tetrahedron) have?
Answer: 4
A tetrahedron has 4 triangular faces — three sloping ones and the base.
How many edges does a triangular pyramid have?
Answer: 6
Three edges around the base and three rising to the apex: 6 edges.
How many vertices does a triangular prism have?
Answer: 6
Three vertices at each triangular end: 6 vertices.
A net is made of 4 triangles. Which solid does it fold into?
Answer: Triangular pyramid
Four triangles fold up into a tetrahedron.
A net is made of 2 triangles and 3 rectangles. Which solid does it fold into?
Answer: Triangular prism
The two triangles are the ends and the three rectangles wrap around the sides.
A solid has 8 faces and 12 vertices. How many edges does it have? (Use faces + vertices − edges = 2.)
Answer: 18
Edges = faces + vertices − 2 = 8 + 12 − 2 = 18.
Which solid has 1 circular face, 1 vertex and 1 curved surface?
Answer: Cone
A cone has a circular base, a curved surface rising to one vertex at the tip.
How many faces does a pentagonal prism have?
Answer: 7
Two pentagonal ends and five rectangular sides: 7 faces.
Which of these cannot be a net of a cube?
Answer: A row of 6 squares
Six squares in a single row fold over each other; two of them land in the same place.
Which solid has the same number of faces, vertices and edges as a cube?
Answer: Cuboid
A cuboid, like a cube, has 6 faces, 8 vertices and 12 edges.