Mathematics

In the diagram above, O is the center of the circle with radius 10cm, and…

In the diagram above, O is the center of the circle with radius 10cm, and ∠ABC = 30°. Calculate, correct to 1 decimal place, the length of arc AC [Take π = 22/7]

  • A.
    5.2cm
  • B.
    10.5cm
  • C.
    13.2cm
  • D.
    20.6cm
  • E.
    31.4cm
Correct Answer: Option B
Explanation

In the figure, < AOC = 2 x < ABC = 60° (angle subtended at the centre)

(therefore) Arc AC = (frac{60}{360} times 2 times 10 times 3.14)

= (frac{31.4}{3})

= 10.466 cm (approxeq) 10.5 cm