Perimeter

Perimeter is a calculation of all the outer side of the shapes .

Formula for perimeter -> Length of Outer side + length of outer side = ____cm @ m.

 

 

Let's us view another example :

 

The calculation for this shape is :

12cm + 10cm + 3cm + 6cm + 6cm ( 12cm - 3cm - 3cm ) + 6cm + 3cm + 10cm = 56cm . 

It is really simple , is it ? 

Remember ! Perimeter only uses '+' . 
If the shape is square , you can multiply the length of outer side .