Definition and Formulas

1. The perimeter of a closed plane figure is the total length of its boundary. To find the perimeter of a figure, add all the lengths of its sides (make sure that the lengths of all its sides are in the same units). 

2. The amount of space contained inside a closed figure is called the area and is measured in square units, e.g. cm2, m2 and km2. 

The image below gives the formula to find the perimeter/area of some basic figures:

More Formulas

The image below gives the formula to find the perimeter/area of more basic figures:

Volumes

1. The volume of a solid is the amount of space it occupies. It is measured in cubic units, e.g. cm3, m3.
2. The volume of liquid/fluid is measured in millilitre (ml), litre (l) or kilolitre (kl).
    1 ml = 1 cm3
    1 l = 1000 ml = 1000 cm3
    1 kl = 1000 l = 1 m3
3. A prism is a solid with uniform cross-sectional area. 
4. A cylinder is a prism with a circle as cross-section. 

The following table gives the formula to find the volume of some common solids. 

Surface Area of Solids

1. The surface area of a solid is the sum of the areas of each of its surfaces.
2. The net of a solid shape is the shape drawn out onto a piece of paper or card in such a way that if you cut round the whole shape you could fold it up into the solid shape. In other words, the net is a plane figure that can be folded up to form a solid.

The table below gives the formula to find the total surface area of some geometrical solids.