The formula for calculating the length of an arc is expressed as
length of arc = θ/360 x 2πr
where
θ represents the angle subtended by the arc at the center of the circle
π is a constant whose value is 3.14
r is the radius of the circle
From the information given,
θ = 6 minutes
We would convert 6 minutes to degrees
If 1 minute = 1/60 degree,
6 minutes = 6/60 = 0.1 degree
r = 390 miles
By substituting these values into the formula,
length of arc = 0.1/360 x 2 x 3.14 x 390
length of arc = 0.680 miles
