# Area of Circles

Explore the formula for the area of a circle, by cutting it into sectors and rearranging the sectors to form a figure close to a parallelogram. By increasing the no. of sectors, students observe that the figure tends to a rectangle and get the formula for the area of the circle by finding the area of this rectangle. See also how I design the applets in http://www.geogebratube.org/material/show/id/15215. 　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　Anthony Or. GeoGebra Institute of Hong Kong. 　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　orchiming@gmail.com （繁體中文版：http://www.geogebratube.org/material/show/id/550）

Resource Type
Activity
Tags
area  circle  circumference  exploration  perimeter  pi
Target Group (Age)
11 – 14
Language
English (United Kingdom)

Views
444626
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