This math topic focuses on calculating the area of a partial sector of a circle. Specifically, it involves determining the area of a green shaded sector that constitutes half of the circle, given the total area of the full circle. The values for the full circle's area are provided, and the learner must apply the concept of fractions to calculate the area of the half-sector. This activity belongs to a broader study area in Geometry concerning partial areas and circumferences of circles. Each problem presents a different total area for the circle and a selection of multiple-choice answers.