Perimeter and areaArea of a combined shape

In this National 4 Lifeskills Maths study guide, you can revise how to find the perimeter and area of triangles, quadrilaterals (rectangle, parallelogram, rhombus, kite and square), circles, arcs, sectors and composite shapes can all be calculated using relevant formulae.

Part ofApplications of MathsGeometry

Area of a combined shape

This shape is made up of a rectangle and a semicircle.

Diagram of a combined shape made up of a rectangle and a semicircle.

To find the total area, find the area of each part and add them together.

Area of the rectangle:

\(= length \times breadth\)

\(= 20 \times 30\)

\(= 600m{m^2}\)

\(Area\, of\, circle = \pi r^{2}\)

\(=\,\pi\times 10 \times 10\)

\(= 314cm^{2}\)

\(Area\,of\,semicircle =\frac{1}{2}\, \times 314 = 157cm^{2}\)

\(Total\, area = 600 + 157\)

\(= 757mm^{2}\)