Two circles of equal radius are located such that each circle passes through the centre of the other circle (see figure). Given that the radius of each circle is \(r\) units, calculate the perimeter of the shape formed by the two circles in terms of \(r\) units. (Ignore the dotted portions that lie within the circles.)
Circumference of one circle \(=\) units.
Circumference of one red arc \(=\) units.
Total Perimeter of red arc \(=\) units.
Answer variants:
\(2 \pi r\)
\(\frac{6\pi r}{3}\)
\(\frac{8\pi r}{3}\)
\(\frac{4\pi r}{3}\)
\(\frac{5 \pi r}{3}\)