Question 418537
How many miles on the surface of the earth correspond to one degree of latitude? (the radius of the earth is 3960)
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There is a formula in trigonometry called the arc length formula:
s=rx, s=arc length, r=radius, x=central angle in radians. This usually applies to a circle but it can apply to the given problem.

s=3960 miles*(1/180)pi radians=3960*3.14/180=69.08 miles
ans:
one degree of lattitude corresponds to 69.08 miles on the surface of the earth.