question_answer

If the region containing pink colour makes an angle of \[30{}^\circ \]at the centre, then find the perimeter of the region containing pink colour.

A) 12.9cm

B) 14.2cm

C) 15.4cm

D) 16.38cm

Correct Answer: D

Solution :

Similarly, Perimeter of the region having pink colour = 2(10 - 6) + length of arc having radius        6 cm + length of arc having radius 10 cm. \[=8+\frac{30{}^\circ }{360{}^\circ }\times 2\times \frac{22}{7}\times 6+\frac{30{}^\circ }{360{}^\circ }\times 2\times \frac{22}{7}\times 10\] \[=8+\frac{7920}{2520}+\frac{13200}{2520}\] \[=8+3.142+5.238\] \[=16.38\,\,cm\]