Four circles of radius 5 cm touch the sides of a square and each other, as shown in the diagram. On each side of the square, an equilateral triangle is drawn to form a four-pointed star.
What is the perimeter of the star?
Select one option, then click Submit.
40 \text{ cm}
80 \text{ cm}
120 \text{ cm}
160 \text{ cm}
200 \text{ cm}
Select an option, then submit.
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Junior Kangaroo 2016 (2016)
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