Math Makes Sense 8 · Unit 4

Nets, surface area and volume

Fold a flat net into the solid and watch each face carry its own area into the formula. Every number updates as you change the dimensions.

Choose an object

Lessons 4.1–4.8 cover these three.

Fold it up

Slide from flat net to finished solid. The faces never change size — that is the whole point of a net.

Dimensions

Measurements are in centimetres.

Every face, every area

Tap a row to pick that face out of the drawing.

FaceHow its area is foundArea

Putting it together

The surface area of an object is the sum of the areas of its faces.

Surface area
Volume