**To find the shaded area of a circle, calculate the area of the full circle and multiply it by the fraction of the circle that is shaded.** The fraction of the circle that is shaded can be determined by dividing the angle that the shaded region covers by 360 degrees.

If 120 degrees of a circle with a radius of 10 centimeters was shaded, the area of the full circle would be 100*pi. Since 120 degrees is exactly one-third of a full circle, multiplying the circle area by 1/3 would yield the shaded area of the circle as 100*pi*1/3, or approximately 104.67 square centimeters.