Mathematics

Problem

An arc of length

10\pi

cm subtends an angle of

\dfrac{2\pi}{3}

radians at the centre of a circle. Calculate (i) the radius of the circle and (ii) the area of the corresponding sector. a)

15\text{ cm},\;150\pi\text{ cm}^{2}

15\text{ cm},\;75\pi\text{ cm}^{2}

20\text{ cm},\;100\pi\text{ cm}^{2}

12.5\text{ cm},\;62.5\pi\text{ cm}^{2}