A regular hexagon and a regular octagon share a common side If the perimeter of the hexagon is 24 cm what is the perimeter of the octagon?

If the perimeter of the hexagon is 24 cm and it is regular, then each side has the same length, namely 24/6 or 4.

Now that is also the length of each side of the octagon since they share a common side so its perimeter is 8x4=32 cm.