Question:
The figure is formed by 2 identical semicircles overlapping each other. The radius of each semicircle is 5 cm. O is the centre of both semicircles. AOB and COD are the diameters. The area of the shaded part OBD is 20 cm² and the perimeter of the shaded part OBD is 18 cm.
(a) Using the calculator value of π, find the area of the figure. Correct your answer to 2 decimal places.
(b) Using π = 22/7, find the perimeter of the figure. Give your answer as a mixed number in the simplest form.
Solution:
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![P6 / CHIJ / 2019 / SA1 / Paper 2 – Q05 [2 marks]](https://i0.wp.com/sgprimaths.com/wp-content/uploads/2020/04/P6_CHIJ_2019_SA1_Paper2_Q05-Qns.jpg?resize=400%2C204&ssl=1)