What is the term for the distance around the outside of a figure?

The distance around the outside of a figure is referred to as the perimeter. Perimeter is a term used in geometry to define the total length of all the sides of a polygon or the boundary length of two-dimensional shapes. For instance, if you consider a rectangle, the perimeter would be the sum of the lengths of all four sides.

In the case of regular shapes like squares, triangles, or other polygons, the perimeter can be easily calculated by adding the lengths of all the sides together. For circles, the term used is circumference, which is a specific type of perimeter that refers to the distance around the circle.

Area measures the amount of space contained within a figure, radius refers to the distance from the center of a circle to its edge, and neither of these terms conveys the concept of distance around a two-dimensional shape like perimeter does. Thus, understanding that perimeter quantifies the boundary distance is key in solving such geometry questions correctly.