The perimeter of a shape is the total length of all of its sides. It is the distance around the outside of a figure or shape. Units of Perimeter Perimeter Formulae

Add the lengths!

Change the units!

First find the missing lengths !

Add up the lengths of all of the sides. Perimeter = 4 + 5 + 8 + 10 
Change units to same type. 500 cm = 0.5 m Perimeter = 1.2 + 1.4 + 0.5 + 0.8 
Calculate the lengths of the missing sides. x = 16 − 8 − 5 = 3 mm Perimeter 