Verified Answer :

circumference = 60PI cm
If an arc is 140 degrees of the circle then its length =

60
PI cm * (140 / 360)
arc length = 23.33333 cm

Answer:

The length of the arc is 73.30 cm.

Step-by-step explanation:

Given : The circumference of a circle is \(60\pi cm\)

To find : What is the length of an arc of 140 degrees.

Solution :

Circumference is \(C=2\pi r\)

\(60\pi=2\pi r\)

\(r=30 cm\)

The radius of the circle is 30 cm.

Angle of arc is \(\theta = 140^\circ\)

The angle is in radian so first we convert into radian as \(1^\circ = \frac{\pi}{180}\)

So, \(140^\circ = \frac{140\pi}{180}\)

The formula of arc length is \(l=r\times \theta\)

Where, l is the length of the arc , r is the radius of circle ,  \(\theta\) is the angle in radian.

Substitute the value in the formula,

\(l =30 \times \frac{140\pi}{180}\)

\(l =73.303cm\)

Therefore, The length of the arc is 73.30 cm.