Original question written by FE Exam AI Prep from the public FE Civil exam specification. Before release, a solver model re-derived the answer twice from the question alone, without its answer key, and a critic model checked the result, and the arithmetic was re-run as an executable calculation. No licensed engineer reviews these questions. It is not an NCEES question and does not come from any NCEES practice exam. FE Exam AI Prep is an independent study tool and is not affiliated with, endorsed by, or sponsored by NCEES.
Latitudes, Departures and Traverse Closure: FE Civil practice problem 5
During an acceptance test record for the Mesa Point detention basin operations upgrade project, the structural checker converts a traverse leg of 340 ft at bearing angle 55 degrees east of north. What northing increment is produced?
- A195.02 ft
- B118.14 ft
- C142.46 ft
- D209.37 ft
Show the answer and worked solution
Answer: A — 195.02 ft
Worked solution
- Step 1. Use northing projection
Delta N = L cos theta
Delta N = 340 cos(55 deg) = 195.02 ft
Why the other choices are wrong
- Choice B
- This value runs about eighteen percent above the correct northing projection, more than any single trigonometric substitution at this bearing angle would generate; recompute the increment as the leg length multiplied by the cosine of the stated bearing angle from north.
- Choice C
- This value equals about seventy-eight percent of the correct northing projection and does not match what swapping sine for cosine, or using the wrong reference angle, would produce at this bearing; multiply the leg length by the cosine of the bearing angle to get the northing increment.
- Choice D
- This value sits roughly forty-five percent above the correct northing projection, a difference too large to trace to one swapped trig function or misread angle; the reliable computation multiplies the leg length by the cosine of the bearing angle measured from north.