Nets of 3-D shapes · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.
En anglais

Nets of 3-D shapes

Mathematics · Geometry · ages 8-11
Name ______________________   Date ____________

  1. A cuboid net has its top and bottom panels. How many more panels cover its sides?

    Answer: ______________

  2. You need one face panel to match the other faces of a cube. Which panel fits?

    • A square half their size
    • A rectangle twice as long
    • A square the same size
    • A triangle with equal sides

  3. What do we call the flat shape that folds up to make a 3-D shape?

    • A net
    • A face
    • An edge

  4. A triangular prism's net is made only of triangles.

    Circle one:   True   False

  5. After a triangular-prism net folds, how many rectangular faces meet each triangular end?

    Answer: ______________

  6. After careful folding, two edges that should join leave a gap. What can you conclude about the folded pattern?

    • It is closed even with that opening
    • It is not a closed solid
    • It must need fewer faces, whatever their positions

  7. Where must the two triangular faces end up when a triangular-prism net folds?

    • Together at one end of the prism
    • Across two long side faces
    • Inside the prism beneath a rectangle
    • At the two opposite ends

  8. In a working net laid flat, two face panels may lie on top of each other.

    Circle one:   True   False

  9. Three patterns use six squares each. Another uses five squares and a triangle. Which can you rule out as a cube net using face shapes alone?

    • The pattern containing a triangle
    • All three patterns containing only squares
    • None: any six face shapes can make a cube

  10. A cuboid net has a 2 cm by 5 cm face. What is the longer side length of its matching opposite face, in centimetres?

    Answer: ______________

LightMySky · lightmysky.comW1-mt_vnJEztczji-s1

Answer key

For grown-ups. Fold this page away before handing over the rest.

Nets of 3-D shapes W1-mt_vnJEztczji-s1

  1. 4 · The remaining faces are front, back, left and right: four panels.
  2. A square the same size · Cube faces match in both shape and size.
  3. A net · A net is the flat pattern of a 3-D shape before it gets folded up.
  4. False · A triangular prism's net has two triangles for the ends and three rectangles for the sides in between.
  5. 3 · Each triangular end has three edges, and each edge meets one rectangular face.
  6. It is not a closed solid · The gap is an opening. The pattern does not form a closed solid while that gap remains.
  7. At the two opposite ends · The triangles close opposite ends. Rectangles connect those ends.
  8. False · The flat pattern lays the face panels out without overlap.
  9. The pattern containing a triangle · A cube has no triangular face. The square-only patterns still need their sizes and positions checked.
  10. 5 · The opposite face also measures 2 cm by 5 cm. Its longer side is 5 cm.
Worksheet · LightMySky