Civil Service Clerical cheat sheet

Conditional validity: from "If P then Q" you may infer the contrapositive "If not Q then not P"; you may not infer the converse "If Q then P" or the inverse "If not P then not Q".

Syllogism chains: "All A are B" plus "All B are C" yields "All A are C"; "All A are B" plus "Some B are C" yields no valid conclusion linking A and C.

In formal logic "some" means "at least one" and is compatible with "all"; it never implies "some but not all" unless the passage states so.

Analogy relation types: synonym, antonym, part-to-whole, category-to-member, cause-to-effect, function-to-object, and degree (warm to hot); the answer pair must match both the relation type and its direction.

True/False/Cannot Say: choose "Cannot say" when the passage neither confirms nor contradicts the statement, including when the statement is plausible but unstated.

A correct main-idea option must cover the entire passage; options that restate one detail, one example, or only the closing sentence are distractors.

Word-in-context questions require the sense that fits the surrounding sentence, which is often not the most common dictionary meaning of the word.

Answers must be supported by the passage alone; general knowledge that is true but absent from the text is not admissible evidence.

Percentage change = (new value − original value) ÷ original value × 100; the divisor is always the starting figure.

Percent of a quantity: convert to a decimal multiplier, e.g. 15% of 240 = 0.15 × 240 = 36; a 20% increase is ×1.20 and a 20% decrease is ×0.80.

Reverse percentage: divide by the multiplier to recover the original, e.g. a value of 96 after a 20% rise came from 96 ÷ 1.20 = 80.

Ratio sharing: sum the ratio parts to get total shares, divide the amount by total shares, then multiply by each part.

Total = mean × count; to combine or extend groups, rebuild each group's total, add or subtract, then divide by the new count.

Profit or loss percentage is calculated on the cost price unless the question explicitly states the selling price is the base.

Simple interest = principal × rate × time ÷ 100, with the rate as an annual percentage and time in years.

Speed = distance ÷ time; convert km/h to m/s by multiplying by 5/18 and m/s to km/h by multiplying by 18/5.

Compare unlike quantities only after conversion: 1 hour = 60 minutes, 1 kg = 1000 g, 1 m = 100 cm, and round only at the final step.

Compare paired strings character by character from left to right and stop at the first mismatch; everything before that point is confirmed correct.

Transposition (45 written as 54, "ei" written as "ie") keeps the same characters but changes the value, so digit and letter order must be checked separately from content.

Look-alike pairs to verify twice: O/0, I/l/1, S/5, B/8, Z/2, rn/m, and doubled versus single letters.

Alphabetical filing is letter by letter with the rule "nothing before something": "Brown" precedes "Browne", and "Brown, A" precedes "Brown, B".

Numeric filing sorts by full value, so 9 precedes 10 and 100 precedes 101; sorting digit by digit produces the wrong order.

Cross-field consistency: listed amounts must sum to the stated total, and a start date must not fall after the corresponding end date.

Date ambiguity: 03/04 can mean 3 April or 4 March, so determine the convention from other entries in the same document before flagging an error.

Proofreading a text from the final word to the first defeats predictive reading, making spelling slips, omissions, and duplicated words visible.

Priority order when duties conflict: safety and legality first, then confidentiality, then customer or stakeholder need, then efficiency, with personal convenience last.

Escalate when a case exceeds your authority, carries risk of harm, or departs from policy; notify the supervisor before acting rather than reporting afterwards.

A documented procedure overrides a customer's preferred shortcut, and only a person with delegated authority can approve a recorded exception.

Confidential information may be shared only with people who have a legitimate need for it; a colleague's curiosity or seniority alone does not create that need.

Disclose your own errors immediately, stating the likely impact and a proposed remedy; delay or concealment converts a minor slip into a serious breach.

When two deadlines collide, protect the task assigned by your line manager and inform the other requester early instead of silently dropping work.

Respond to rudeness by addressing the specific behaviour or problem in a neutral tone; repeated abuse is handled through the formal channel, not by retaliating.

Situational tests reuse similar scenarios, so answers are scored for consistency; apply the same principles across every item rather than optimizing each one separately.