Area of a circle

The formula to calculate the area of a circle, with radius r is: \text{area of a circle} = \pi r^2

Example

Calculate the area of the clock face. Give your answer to one decimal place.

Clock face with radius, 8cm

\text{Area} = \pi \times 8^2

Remember to use BODMAS. The radius must be squared first before multiplying by \pi.

The exact value for the area is = 64\pi. Rounded to 1 decimal place, the area is 201.1 cm2.