How do you do size of sector?

To determine the size of a sector in a circle, you can use the formula: Area of the sector = (θ/360) × πr², where θ is the central angle of the sector in degrees and r is the radius of the circle. If you have the angle in radians, the formula becomes: Area of the sector = (1/2) × r² × θ. This allows you to calculate the area based on the proportion of the circle that the sector represents.