Similar to Problem 4.28, except a plus sight of 7.44 ft is taken on BM A and a minus sight of 1.55 ft read on point X.
Problem 4.28:
If a plus sight of 3.54 ft is taken on BM A, elevation 850.48 ft, and a minus sight of 7.84 ft is read on point X, calculate the HI and the elevation of point X.