City A is due north of City B Find the distance between City

City A is due north of City B. Find the distance between City A (40degree8\' north latitude) and City B (20degree56\' north latitude). Assume that the radius of Earth is 3960 miles. The distance between City A and City B is miles. (Round to the nearest mile as needed.)

Solution

Curve length = radius*angle = 3960*(1*pi/180) = 69.115 miles.

So, 1 degree corresponds to 69.115 miles on earth

we have angle between the two cities = 40deg8\' -20deg56\' = 40.133 - 20.933 = 19.2 deg

So, distance between the two = 19.2 * 69.115 = 1326.98 = 1327 miles