Sometimes we need to find out what is the distance around a particular object. This measurement is called the perimeter.

Let’s calculate the perimeter of this table. What do you think we need to do first?

That’s right. We have to measure each side. The metre ruler would be best for this job. Okay, the first side measures two metres, the next side measures one metre, next side measures two metres again. And the last side measures one metre. Now we add them all up, two metres plus one metre equals three metres, three metres plus two metres equals five metres. And five metres plus one metre equals six metres. So the perimeter of this table is six metres.