Reasoning from Rules Questions: How to Work a Rule Sheet

Reasoning from Rules tests whether you can apply a written rule exactly. EEI's TECH brochure says it measures the ability to read and apply rules to make decisions and to troubleshoot a logic network. In practice that means two kinds of question: a short sheet of if-then rules with cases to decide, and a small network of logic elements to work through. Neither needs outside knowledge — and outside knowledge is usually what gets people into trouble.

What EEI publishes about it

The brochure gives the description above and one example, built around scheduling machines by product grade and region. It does not give a question count or a time limit; of the four TECH tests, only Mechanical Concepts has those. LG&E and KU describes the skill area as decision-making or troubleshooting through rules application. Our practice runs 24 questions in 30 minutes, which is our own pacing, not EEI's.

Our rule sheets are original and set in technician work — a chemistry lab's sample intake, relay testing, drawing changes, work orders, telecom tickets, a meter shop, a test-equipment store and more. Every rule on them is invented for practice. We do not copy or adapt EEI's example.

Rule sheets: the four habits

1. Go in order and stop at the first rule that fits. Most sheets are written so that a case can satisfy more than one rule. The earlier rule wins. If you read the whole sheet and pick the rule that "fits best", you will be wrong exactly when it matters.
2. Check every condition. A rule with two conditions applies only when both hold. Tick them off; do not stop at the first match.
3. Read the boundaries literally. "Over 48 hours" does not include 48. "48 hours or more" does. "Under $1,000" does not include $1,000. Question writers put case values exactly on the boundary on purpose.
4. Use only the sheet. If your lab would never reject a sample that is 72 hours old, it does not matter: the sheet says reject. The rules are the whole world of the question.

Worked example: a rule sheet

You log samples at a lab. Apply the rules in order; use the first that fits.

1. If the age of the sample is over 48 hours: reject it and ask for a new sample.
2. If the source is transformer oil: send it to the oil lab.
3. If the priority is Rush and the volume is 250 mL or more: Bench 1.
4. If the source is boiler water or cooling tower: Bench 2.
5. In all other cases: hold it in the refrigerator.

Case: cooling-tower water, Rush, 48 hours old, 250 mL. Rule 1 does not fit — 48 is not over 48. Rule 2 does not fit. Rule 3 fits: Rush, and 250 mL is "250 mL or more". So: Bench 1. Rule 4 would also fit — it is cooling-tower water — but it never gets a turn.

Two other question shapes test the same habits from different angles. "Which of these four samples goes to Bench 2?" makes you run the sheet four times; do it quickly by checking the early rules that would intercept each case. And "Which one change would send this sample to the refrigerator instead?" makes you think about which conditions are doing the work — usually the answer is the change that knocks out the rule currently deciding the case without triggering an earlier one. The Reasoning from Rules demo has all of these.

Logic networks: work box by box

The second half of the description — troubleshooting a logic network — is where many candidates freeze, usually because they expect electronics. Our networks state their rules on the page: switches set ON or OFF feed boxes, each box follows a stated rule, and the last box lights a lamp.

• AND box: ON only when both inputs are ON.
• OR box: ON when at least one input is ON.
• NOT box: the opposite of its one input.
• ONE box: ON when exactly one of its two inputs is ON.

Work left to right, writing each box's output beside it. Never skip a box because you "can see" the answer; that is how errors propagate.

Worked example: which box has failed?

Switch A is ON and B is OFF, feeding an AND box (Box 1). Switch C is OFF, feeding a NOT box (Box 2). Boxes 1 and 2 feed an AND box (Box 3), which drives lamp Z. A technician reads: Box 1 OFF, Box 2 ON, Box 3 ON, lamp ON. Exactly one box has failed. Which?

Check each box against its rule using the inputs it is actually getting — the switch settings, or the readings of the boxes that feed it. Box 1: AND of ON and OFF is OFF; it reads OFF, so it is fine. Box 2: NOT of OFF is ON; it reads ON, fine. Box 3: AND of OFF (Box 1) and ON (Box 2) should be OFF, but it reads ON. Box 3 has failed. The lamp is fine — it shows what Box 3 is sending it.

The key move is judging each box by its real inputs, not by what its inputs "should" be. If an early box fails, the boxes after it are fed the wrong signal and still behave correctly; blaming them is the classic mistake.

Practising it

This test rewards a routine more than talent, which makes it one of the best uses of practice time in TECH — see what EEI publishes about TECH for how it fits with the other three tests, and Interpreting Diagrams for its closest neighbour. Our TECH practice draws from twenty-two invented rule sheets and generated networks, explains each answer step by step, and runs a full practice mock alongside the other three TECH tests. Dominion Energy, which uses the EEI batteries for many craft, skilled trades and technical positions, also points applicants to EEI's practice tests — use both.

Frequently asked questions

Is Reasoning from Rules a logic puzzle test?

Partly. The rule-sheet questions are about applying written procedures exactly; the network questions are small logic puzzles with their rules stated on the page. Neither needs prior knowledge.

How long is the Reasoning from Rules test?

EEI does not publish a count or a time limit for it. Our 24-in-30 practice run is our own pacing.

What is the most common mistake?

Choosing the rule that fits best instead of the first rule that fits, closely followed by misreading "over" as "or more".