Be systematic! What sort of numbers are important to help you solve this problem?
How many triangles are in this shape? (A Transum starter)
When you are absolutely sure you have counted them all, click here and press the yellow button to see if you are right.
This square based pyramid has 5 faces, 5 vertices and 8 edges.
See how quickly you can do this quiz from Purpose Games. Click start, then the computer will give you a number for either F (faces), V (Vertices) or E (Edges). You just have to click on the letter next to the right shape.
Do you know your prisms from your pyramids? See how quickly you can do this quiz from Purpose Games. Click start, then click on the shape whose name appears at the top.