5.2 Classification, Ordering, and Pattern Rules
Key Takeaways
- Classification questions sort an item after every stated condition is checked in the correct priority.
- Ordering questions become easier when fixed positions and locked blocks are placed before flexible items.
- Pattern questions usually depend on one repeated operation, changing differences, or an alternating sequence.
- Words such as before, after, immediately, either, both, and except determine whether a rule creates a slot, category, or exclusion.
Rule-Based Sorting and Sequencing
Civil service logic questions often look like normal office tasks. You may route applications, rank interview packets, place workers on a schedule, or continue a number series. The content changes, but the work is the same: identify the rule type, set up the information, and eliminate anything that violates a stated condition.
A classification rule tells you what category an item belongs in. An ordering rule places items before, after, beside, first, or last. A pattern rule asks what operation turns one term into the next.
Choose the Right Setup
Do not solve every logic item in your head. A small setup prevents memory errors and makes wrong answers easier to spot.
| Clue in the Question | Best Setup | First Move |
|---|---|---|
| assigned to, classified as, route to | Category table | List the categories and required conditions |
| before, after, first, last | Slots or timeline | Place fixed positions first |
| immediately before or next to | Locked block | Keep the items together while arranging |
| more than, fewer than, higher than | Ranking ladder | Put greatest and least at the ends if known |
| next term or missing term | Difference list | Compare gaps, ratios, or alternating moves |
Classification Example
Rule: Route a request to Desk A if it is urgent or received before noon. Route it to Desk B if it is not urgent and received at noon or later. A request received at 2:40 p.m. and marked urgent goes to Desk A.
The word or matters. Either condition is enough for Desk A. Late receipt does not override urgency. A rushed test taker may see 2:40 p.m. and choose Desk B, but that ignores the first condition.
Classification questions may also use priority rules. If a rule says that fraud allegations go to Investigations even when another category applies, check that exception first. Specific rules usually beat general rules when the question states a priority.
A useful office example is a benefits packet marked expedited, incomplete, and signed. If expedited packets go to supervisor review before all other routing, the packet goes to supervisor review first. Do not send it to the incomplete-file queue unless the rules say incompleteness outranks expedited handling.
Ordering Example
Suppose five packets must be reviewed: Budget, Intake, Licensing, Records, and Zoning. The rules say Budget is before Licensing, Intake is immediately before Records, and Zoning is not first.
Treat Intake-Records as a locked block. Then place Budget somewhere before Licensing. Zoning can fill any remaining slot except the first. The setup might look like this: _ _ _ _ _, with [Intake Records] moving as one piece until the other rules force a position.
If the question asks what must be true, look for relationships that appear in every valid arrangement. If it asks what could be true, a single arrangement is enough. Mixing up must and could is a common source of lost points on ordering items.
Ordering Trap Table
| Trap | Example | How to Avoid It |
|---|---|---|
| Separating a block | Puts Intake in slot 2 and Records in slot 5 | Mark immediate rules as a single unit |
| Treating before as immediately before | Requires A right next to B when the rule only says before | Allow space unless the rule says immediately |
| Forgetting a negative rule | Places Zoning first despite not first | Write not rules beside the slots |
| Assuming one valid order | Stops after finding one arrangement | Test the answer choice actually asked |
| Missing either-or | Requires both alternatives | Ask whether the rule says either, both, or at least one |
Pattern Example
For 7, 12, 20, 31, 45, write the differences: +5, +8, +11, +14. The differences increase by 3, so the next difference is +17 and the next term is 62.
For letters, convert to positions when the pattern is not obvious. C, F, J, O becomes 3, 6, 10, 15. The gaps are +3, +4, +5, so the next gap is +6 and the next position is 21, or U.
Efficient Elimination
Start with the most restrictive rule. Fixed first or last positions, immediate blocks, and no rules remove choices quickly. For classification, test each item against the highest-priority condition before broad categories. For sequences, try constant differences before more complex operations.
When two answer choices seem possible, reread the question stem. It may ask which order is valid, which item must be first, which category is required, or which term comes next. Those are different tasks, and the setup should answer the exact one asked.
A routing rule says: Code Green files are complete and signed. Code Yellow files are missing at least one attachment but include current contact information. Code Red files lack current contact information. A file is signed, missing one attachment, and includes current contact information. How should it be classified?
Five tasks are arranged in one row: Budget, Briefing, Inspection, Outreach, and Records. Budget must be before Briefing. Briefing must be immediately before Inspection. Records must be after Inspection. Outreach cannot be first. Which order is valid?
What number comes next in the sequence: 6, 11, 19, 30, 44, ___?