Irish Defence Forces Cadetship Aptitude Assessment cheat sheet

Word-analogy links to test in order: synonym, antonym, part-to-whole, member-to-category, cause-to-effect, worker-to-tool, degree of intensity, function.

Valid chain: All A are B + All B are C → All A are C. Invalid: All A are B + Some B are C → Some A are C.

Contrapositive is always valid: from 'All A are B' infer 'All non-B are non-A'. The converse 'All B are A' is not valid.

'No A are B' converts cleanly to 'No B are A'; 'Some A are B' converts to 'Some B are A'.

In formal logic 'some' means at least one and possibly all - it never implies 'some are not'.

Odd-one-out: identify the property shared by four of five options, then test each candidate as the exception against that majority rule.

Letter series: A=1 … Z=26; pairs symmetric about the alphabet sum to 27 (A+Z, B+Y, C+X); steps are usually ±1, ±2, alternating, or mirrored.

Passage-based items: the correct option is supported by the printed text alone; outside knowledge and plausible inference are not evidence.

Check part of speech before meaning in classification items - a verb among nouns is out regardless of topic.

Percentage change = (new − old) ÷ old × 100. Increase by p% multiplies by (1 + p/100); decrease by p% multiplies by (1 − p/100).

Original value from a result: if a price after a 20% rise is 96, original = 96 ÷ 1.20 = 80 - never subtract 20% of 96.

Average = sum ÷ count, so sum = average × count; adding a value above the average raises the mean, below it lowers the mean.

Ratio a:b has a+b parts; each share = (its part ÷ total parts) × whole amount.

Speed = distance ÷ time; 1 m/s = 3.6 km/h (multiply by 3.6 to convert, divide to reverse).

Combined work: rates add, so two workers taking a and b hours together take ab/(a+b) hours.

Simple interest I = P×R×T ÷ 100. Compound amount A = P(1 + r)^n with r as a decimal rate per period.

Profit or loss percentage is always based on cost price: (selling − cost) ÷ cost × 100.

Number series: test differences, then second differences, then ratios, then alternating and square/cube/prime patterns; round to two significant figures to eliminate options quickly.

Track attributes separately: shape type, number of sides, size, fill/shading, rotation angle, and position. Usually one varies per step.

Alternating series: if changes look irregular, split into odd-positioned and even-positioned terms and find a rule for each.

Rotation is most often 90° clockwise per step; count sides, vertices, and lines of symmetry - these often form the sequence (e.g. 3, 4, 5, 6).

Overlay rules: XOR keeps lines appearing in exactly one figure and deletes shared lines; addition keeps everything; subtraction keeps only lines unique to the first.

In a 3×3 matrix the rule must hold across every row and down every column - verify the answer in both directions.

Enclosed regions, intersections, and symmetry axes are common hidden attributes - count them explicitly for the stem and each option.

A reflected figure cannot be produced by rotation in the plane; check whether the handedness of an asymmetric feature has flipped.

If two options satisfy your rule, the rule is too broad - find an additional attribute that isolates exactly one option.

Cube net: faces separated by exactly one face in a straight line become opposite faces and never share an edge.

Cube facts: 6 faces, 12 edges, 8 vertices; Euler's relation V − E + F = 2.

Painted n×n×n cube: 8 cubes with 3 painted faces, 12(n−2) with 2, 6(n−2)² with 1, and (n−2)³ with none.

Vertical mirror reverses left-right and preserves top-bottom; water image reverses top-bottom and preserves left-right.

Rotation preserves shape, size, and handedness; reflection preserves shape and size but reverses handedness.

Folding a net: pick a base face, fold neighbours up 90°; faces joining at a net edge share an edge on the cube.

Paper punch: unfold in reverse order of folding, reflecting the holes across each fold line; holes double per fold unless they overlap.

Orthographic views: front elevation = width and height; plan/top view = width and depth; side view = depth and height.

Lever balance: F₁ × d₁ = F₂ × d₂, with distances measured perpendicular from the pivot.

Mechanical advantage = load ÷ effort; for a lever it also equals effort arm ÷ load arm. MA > 1 multiplies force.

Single fixed pulley: MA = 1, changes direction only. Movable pulley supported by n rope sections: MA = n.

Inclined plane: MA = length of slope ÷ vertical height. Wheel and axle: MA = R ÷ r.

Gear ratio = teeth driven ÷ teeth driving; meshing gears rotate in opposite directions, gears on one shaft rotate together at the same speed.

Hydraulics (Pascal's law): F₁/A₁ = F₂/A₂ - small piston, small force; large piston, proportionally larger force.

Pressure = force ÷ area, so the same force over a larger area gives lower pressure (wide tyres, snowshoes).

Float or sink: an object floats if its density is less than the fluid's, sinks if greater, and is neutrally buoyant if equal.

Bimetallic strip bends towards the metal with the lower expansion coefficient when heated; work = force × distance, power = work ÷ time.

These items measure typical behaviour and preference, not ability - there is no correct answer, but profiles are compared against role criteria.

Forced-choice items ask you to pick the more and least like you from equally desirable statements; answer from one stable self-view.

Consistency scales repeat similar content in different wording; contradictory answers lower the consistency indicator.

Social desirability scales flag answers almost nobody endorses; occasional admission of ordinary weakness keeps the profile credible.

Likert items: the midpoint means neutral or undecided and carries little information - reserve it for genuinely indifferent items.

Infrequency and response-time checks detect random or rushed responding, so read each item fully before answering.

Defence-forces competencies assessed: teamwork, integrity, leadership potential, resilience under stress, adaptability, communication, and rule-following.

Answer in terms of what you actually do at work or in sport or study, not what sounds most impressive to a selector.

There is no pass mark on personality; the report describes a profile, so consistency matters more than any single item.

Items often come in pairs where both statements are positive - choose the one that is more true more of the time.

Avoid answering every item identically at the extreme; a fully extreme profile is treated as less reliable.