Remarkable / Worksheets / Grade 7 Maths / Surface area and volume of 3D objects
A one-page CAPS Grade 7 Maths poster on surface area and volume of 3D objects (Measurement), with the key ideas, key words and a tip to remember.
Volume is the space inside a solid. It is measured in cubic units such as cm³ and m³.
A box is 7 cm by 5 cm by 2 cm.
V = 7 × 5 × 2 = 70 cm³
Surface area is the total area of all the faces of a solid. Its unit is cm² or m².
A box is 6 cm by 3 cm by 2 cm.
l × b = 18, l × h = 12, b × h = 6
SA = 2 × (18 + 12 + 6) = 72 cm²
A tank is 20 cm by 10 cm by 15 cm.
V = 3 000 cm³ = 3 000 ml = 3 l
A cube has 6 equal square faces. A rectangular prism has 6 rectangular faces. Opposite faces are equal.
If you know the volume of a cube, find the cube root to get the length of an edge.
V = 27 cm³, so s = ∛27 = 3 cm
SA = 6 × 3 × 3 = 54 cm²