The diagram below shows a sector of a circle - AQA - A-Level Maths Mechanics - Question 3 - 2019 - Paper 1

To find the area of a sector of a circle, the formula is given by:

$A = \frac{\theta}{2} \times r^2$

where:

• $\theta$ is the angle in radians,
• $r$ is the radius of the circle.

Substituting the values into the formula:

$A = \frac{0.8}{2} \times 4^2$

Calculating this gives:

$A = 0.4 \times 16 = 6.4 \text{ cm}^2$

Thus, the area of the sector is 6.4 cm².