11.3 Approved Calculator Habits

Use a permitted calculator-and only that calculator

NCEES publishes an approved-calculator policy that is updated yearly, and only models on the current list are allowed into the test center. Programmable, graphing, and communication-capable calculators are prohibited and will be confiscated by the proctor. The practical rule: pick an approved model now, and make it the only calculator you use for the entire prep cycle. Switching models in the final week is a self-inflicted error-menu layouts, memory-recall keys, and degree-minute-second (DMS) entry differ enough between models to cause exam-day mistakes under pressure.

The approved FS-friendly models generally fall into three families. The table below shows the trade-offs you are choosing between:

Bring a backup of the same family if rules allow; a dead calculator with no replacement is an avoidable disaster on a 5+ hour exam.

The errors a calculator routine prevents

Most FS computation losses are not formula-knowledge gaps-they are mechanical slips that the question writers anticipate and offer as distractors. The four big ones:

1. Angle mode (DEG vs RAD vs GRAD). A trig answer computed in radians instead of degrees is wrong by a large factor and often matches a listed wrong answer. Set DEG at the start and re-verify it whenever a result looks off. Surveying uses degrees (and DMS); least-squares or some advanced work may want radians-know which the current item needs.
2. DMS entry and conversion. Bearings and angles are given in degrees-minutes-seconds. Practice your model's DMS-to-decimal and back keystrokes until they are automatic; a mis-keyed minutes/seconds value silently corrupts a coordinate.
3. Sign and quadrant. Latitudes and departures carry signs by quadrant (NE: +N,+E; SE: -N,+E; SW: -N,-E; NW: +N,-E). Dropping a sign sends a coordinate to the wrong quadrant-another favorite distractor.
4. Premature rounding. Rounding intermediate values and then chaining them propagates error into the final answer. The discipline below fixes this.

Use this bearing/azimuth keystroke routine every time: (a) confirm DEG mode; (b) enter the angle in DMS using the dedicated key; (c) compute latitude = distance x cos(azimuth), departure = distance x sin(azimuth); (d) apply the quadrant sign; (e) store the running coordinate in memory, not on paper.

Keep precision, then sanity-check

The single most valuable calculator habit is carry full precision in memory and round only the final answer. Surveying chains many operations-bearing, distance, coordinate, area-and each premature round injects error that can push you off the correct choice. Store intermediate coordinates in registers and recall them; do not transcribe 8-digit numbers to scratch paper and re-key them (a re-keying typo is a classic blunder).

Then run a reasonableness check before selecting an answer:

• Order of magnitude: Is the area in the right thousands of square feet? Is the curve length comparable to the radius times the central angle in radians?
• Sign/quadrant: Does the resulting bearing point the direction the sketch implies?
• Units: Did the problem give meters but the choices read in feet (or acres vs. square feet)? The FS exam mixes SI and U.S. Customary units, so a units mismatch is built into the test.
• Bracketing: Estimate the answer to one significant figure mentally; if your calculator result is 10x off, you likely have an angle-mode or decimal-place error.

A five-second reasonableness pass is the cheapest insurance on the exam, because the distractors are specifically engineered to look plausible when you make exactly these mistakes.

Drill the keystroke routines that recur

Certain calculator routines appear over and over on the FS exam, and each should be automatic before exam day-rehearsed until you no longer look at the keys. Build and time these:

• DMS <-> decimal degrees: convert a bearing like 42 deg 17' 30" to decimal and back. Mis-keying minutes/seconds is a silent coordinate corrupter.
• Bearing/azimuth conversions: translate between quadrant bearings (N 42 deg E) and full-circle azimuths, and apply the correct latitude/departure signs by quadrant.
• Coordinate inverse: given two coordinates, return the distance and bearing between them-the backbone of COGO problems.
• Statistics mode: enter a data set and read off mean and standard deviation directly, rather than computing by hand.
• Memory store/recall: park a running coordinate or intermediate value and recall it, instead of re-keying.

A short keystroke table keeps your routines consistent across practice sessions:

Treat the calculator as an instrument you are certified on. The candidate who fumbles a DMS conversion or hunts for the statistics menu during the exam loses both time and confidence; the candidate whose routines are reflexive spends that energy on the surveying, not the keys.