Q.4 A gardener wants to fence a circular garden of diameter 21m. Find the length of the rope he needs to purchase, if he makes 2 rounds of fence. Also find the cost of the rope, if it costs Rs. 4 per meter. (Take $$\pi = \frac{22}{7}$$)
$$\therefore Radius = \frac{21}{2}$$ m
$$\therefore$$Circumference =$$2\pi r = 2×\frac{22}{7}×\frac{21}{2} = 66 m$$