Three circles of radius 4 cm are kept touching each other. The string is tightly tied around these three circles. What is the length of the string?

Solution (By Examveda Team)

$$\eqalign{ & = 3 \times 2\sqrt {Rr} \cr & = 3 \times 2\sqrt {4 \times 4} \cr & = 24 \cr & = 24 + 2\pi r \cr & = 24 + 2\pi \times 4 \cr & = 24 + 8\pi {\text{ cm}} \cr} $$