Question

An arc of a circle subtends an angle of 30o
on the
circumference of a circle of radius 21cm. Find the
length of the arc.
A. 11cm
B. 22cm
C. 44cm
D. 66cm

Answer 1

To find the length of the arc, we need to use the formula for the arc length:

arc length = (angle/360) * 2 * π * radius

Given that the angle is 30° and the radius is 21 cm, we can plug these values into the formula:

arc length = (30°/360) * 2 * π * 21 cm

Simplifying the fraction:

arc length = (1/12) * 2 * π * 21 cm

Multiplying:

arc length = (1/6) * π * 21 cm

Now, we can calculate the approximate value of π using 3.14:

arc length ≈ (1/6) * 3.14 * 21 cm

arc length ≈ 3.49 cm

Therefore, the length of the arc is approximately 3.49 cm.

None of the answer choices A, B, C, D match this value, so it seems there might be an error in the question or the answer choices.