Practice!

Sample Problem

Mr. Whale used a piece of wire to make the two shapes below. If he had 15 cm of wire left, what was the original length of the wire?

cm

Solution

Perimeter of the first shape: 6 cm + 8 cm + 6 cm + 8 cm = 28 cm

Perimeter of the second shape: 8 cm + 10 cm + 8 cm + 10 cm = 36 cm

The length of the wire: 28 cm + 36 cm + 15 cm = 79 cm