Shapes Around Us
Which solid am I?
Solve riddles where solid shapes describe themselves.
In your book, Maths Mela (Chapter 1), some solids tell you riddles about themselves: 'I have ... faces, ... corners and ... edges. Who am I?' To answer, check each clue against the solids you know.
'I have 5 faces, 5 corners and 8 edges. 1 face is a square and 4 are triangles.' That is a square pyramid. 'I have 5 faces, 6 corners and 9 edges, and 2 of my faces are triangles.' That is a triangular prism. Both have 5 faces, so the corners and edges tell them apart.
Some riddles are about curved faces. An edge is where two faces meet, and on a round solid that edge is a curved line. 'I have 1 flat face, 1 curved face and 1 edge' is a cone: its round bottom meets its curved face in one edge. 'I have 2 flat faces, 1 curved face and 2 edges, and no corners' is a cylinder: each round end meets the curved face in its own edge. 'I have 1 curved face and no edges or corners' is a sphere, a ball.
'I have 6 faces, 12 edges and 8 corners.' This could be a cube or a cuboid, because they have the same numbers. If every face is a square, it is a cube.
Practise this lesson
Questions that get harder as you improve, a Tutor that helps without giving the answer away, and progress you can see. Free for every learner.
No account, no email address. Opens the real product.