Have a go at this 3D extension to the Pebbles problem.
These formulae are often quoted, but rarely proved. In this article, we derive the formulae for the volumes of a square-based pyramid and a cone, using relatively simple mathematical concepts.
What size square corners should be cut from a square piece of paper to make a box with the largest possible volume?
A box has faces with areas 3, 12 and 25 square centimetres. What is
the volume of the box?
An irregular tetrahedron has two opposite sides the same length a
and the line joining their midpoints is perpendicular to these two
edges and is of length b. What is the volume of the tetrahedron?
Use a single sheet of A4 paper and make a cylinder having the greatest possible volume. The cylinder must be closed off by a circle at each end.
What is the volume of the solid formed by rotating this right
angled triangle about the hypotenuse?
What is the greatest volume you can get for a rectangular (cuboid)
parcel if the maximum combined length and girth are 2 metres?
Imagine two identical cylindrical pipes meeting at right angles and think about the shape of the space which belongs to both pipes. Early Chinese mathematicians call this shape the mouhefanggai.
Here's a chance to work with large numbers...
This jar used to hold perfumed oil. It contained enough oil to fill
granid silver bottles. Each bottle held enough to fill ozvik golden
goblets and each goblet held enough to fill vaswik crystal. . . .
Practice your skills of measurement and estimation using this interactive measurement tool based around fascinating images from biology.
According to Plutarch, the Greeks found all the rectangles with
integer sides, whose areas are equal to their perimeters. Can you
find them? What rectangular boxes, with integer sides, have. . . .
My measurements have got all jumbled up! Swap them around and see
if you can find a combination where every measurement is valid.
Can you rank these sets of quantities in order, from smallest to largest? Can you provide convincing evidence for your rankings?
The builders have dug a hole in the ground to be filled with concrete for the foundations of our garage. How many cubic metres of ready-mix concrete should the builders order to fill this hole to. . . .
What happens to the area and volume of 2D and 3D shapes when you
Can you sketch graphs to show how the height of water changes in
different containers as they are filled?
How can you change the surface area of a cuboid but keep its volume the same? How can you change the volume but keep the surface area the same?
Can you choose your units so that a cube has the same numerical value for it volume, surface area and total edge length?
If I don't have the size of cake tin specified in my recipe, will the size I do have be OK?
Analyse these beautiful biological images and attempt to rank them in size order.
Imagine different shaped vessels being filled. Can you work out
what the graphs of the water level should look like?
Can you draw the height-time chart as this complicated vessel fills
In the ancient city of Atlantis a solid rectangular object called a
Zin was built in honour of the goddess Tina. Your task is to
determine on which day of the week the obelisk was completed.
If the radius of the tubing used to make this stand is r cm, what is the volume of tubing used?
A right circular cone is filled with liquid to a depth of half its
vertical height. The cone is inverted. How high up the vertical
height of the cone will the liquid rise?
A plastic funnel is used to pour liquids through narrow apertures.
What shape funnel would use the least amount of plastic to
manufacture for any specific volume ?
An aluminium can contains 330 ml of cola. If the can's diameter is
6 cm what is the can's height?
An activity for high-attaining learners which involves making a new cylinder from a cardboard tube.
It is known that the area of the largest equilateral triangular
section of a cube is 140sq cm. What is the side length of the cube?
The distances between the centres of two adjacent faces of. . . .
Various solids are lowered into a beaker of water. How does the
water level rise in each case?