Question

Forbearing and back bearing of the lines of a traverse are as follows:

Line	AB	BC	CD	DE
For bearing (degree)	125	172	264	316
Back bearing (degree)	304	351	83	136

Which of the following station is free from the local attraction?

Answer 1

Line	For bearing (F.B)	Back bearing (B.B)	FB-BB
AB	125	304	-179
BC	172	351	-179
CD	264	83	181
DE	316	136	180

$\bullet$ If the difference between the fore and back bearing of the line is ${180}^0$, then both the end stations are considered to be free from local attractions provided the compass is not having any instrumental error.

$\bullet$ Since the difference of fore bearing & back bearing of line DE is ${180}^0$ so stations D and E are considered to be free from local attractions.