In the diagram above, O is the center of the circle with radius 10cm, and ∠ABC = 30^\circ. Calculate, correct to 1 decimal place, the length of arc AC [Take \pi = 22/7]
Attached Figure / Diagram
A
5.2cm
B
10.5cm
C
13.2cm
D
20.6cm
E
31.4cm
Verified Correct Answer: B.
Step-by-Step Mathematical Solution
In the figure, < AOC = 2 x < ABC = 60^\circ (angle subtended at the centre)
\(\therefore\) Arc AC = \(\frac{60}{360} \times 2 \times 10 \times \frac{22}{7}\)
= \(\frac{31.4}{3}\)
= 10.466 cm \(\approxeq\) 10.5 cm
Source: Myschool Past Questions Archive (Record #22650)