Problem 45 Solution

Take the sum of the rings going around the earth from the 37th to the 41st lines of latitude. This is the integral from 37 to 41 of the cosine of x dx. Integrate this and you get sin(41)-sin(37). Divide this by 2 since this is only relative to the northern hemisphere. Then multiply by (109-102)/360 for its share of the earth's longitude.

Michael Shackleford, A.S.A.