GCE A/L Common General Test cheat sheet

Analogy direction rule: establish the exact relation in the stem pair (part-to-whole, cause-effect, synonym, degree, function) and apply it in the same direction; a reversed relation is a wrong option.

Odd-one-out test: classify each word by the same criterion (word class, semantic field, prefix origin, syllable stress); the outlier is the only item that fails the shared criterion.

Antonym/synonym traps: options that are merely associated with the keyword are distractors; the answer must match the precise sense, not a related idea.

Syllogism in words: 'All A are B' does not imply 'All B are A'; only valid conversions are 'Some A are B' and 'Some B are A'.

Reading comprehension: answers must be supported by the passage text; outside knowledge and plausible inference are not evidence unless the question asks for inference.

Prefix meanings: anti- (against), circum- (around), hyper- (over/excess), hypo- (under/deficient), mal- (bad), mis- (wrongly), post- (after), pre- (before), sub- (under).

Sentence correction: subject-verb agreement, pronoun antecedent, parallel structure, and misplaced modifier are the four error types tested most often; check these before style.

Word-length and letter-position puzzles: number letters from 1 at the left; the nth letter from the right in a word of L letters is the (L - n + 1)th from the left.

Percentage change: increase then decrease of the same rate r% gives net change of -r²/100 %, never zero.

Successive percentage changes a% and b% combine as a + b + ab/100.

Average speed for equal distances at speeds x and y is the harmonic mean 2xy/(x+y), not (x+y)/2.

Work problems: if A finishes in a days and B in b days, together they take ab/(a+b) days.

Compound interest: A = P(1 + r/100)^n; simple interest: SI = PRT/100. The gap between them grows with n.

Ratio scaling: if a:b = 2:3, write amounts as 2k and 3k; total = 5k. Solve for k, then substitute.

Profit and loss: profit% is calculated on cost price unless stated otherwise; selling price = CP × (100 + profit%)/100.

Divisibility: by 3 or 9 if the digit sum is divisible by 3 or 9; by 4 if the last two digits form a multiple of 4; by 11 if alternating digit sums differ by a multiple of 11.

Mixtures: replacement formula final quantity of pure component = initial × (1 - replaced/total)^n.

Contrapositive is always valid: from 'If P then Q' infer 'If not Q then not P'. The converse ('If Q then P') is invalid.

'Only if' reverses the arrow: 'P only if Q' means P → Q, not Q → P.

'Unless' means 'if not': 'P unless Q' translates to 'If not Q then P'.

Negation of 'All A are B' is 'Some A are not B'; the negation of 'Some A are B' is 'No A are B'.

Seating/ordering puzzles: fix the most constrained item first, then place items with two or more given relations; verify each derived position against every clue.

Blood relations: draw a family tree with gender markers; 'brother of my father' = uncle, 'son of my sister' = nephew.

Number/letter series: check differences, then second differences, then ratios; alternating series often interleave two independent patterns.

Truth-teller puzzles: assume one speaker truthful and test for contradiction; the consistent assignment is the answer.

Syllogism with 'some': two 'some' premises yield no valid conclusion; one 'all' plus one 'some' yields a 'some' conclusion only.

Rotation preserves shape and size; reflection reverses orientation (chirality), so a reflected figure cannot be rotated into the original.

Clock-angle formula: angle between hands = |30H - 5.5M| degrees; adjust to the smaller angle by subtracting from 360 if over 180.

Mirror image: left and right swap, top and bottom stay; water image: top and bottom swap, left and right stay.

Paper folding: each fold doubles the number of symmetric holes; count punch positions before unfolding, then mirror across every fold line.

Cube nets: a valid net has 6 squares and folds without overlap; opposite faces are separated by one square in a straight line of the net.

Counting figures: count smallest units first, then combinations of adjacent units; total = sum over sizes of possible contiguous blocks.

Embedded figures: the target shape must appear with the same proportions and orientation as drawn; distorted or rotated variants do not count.

Dice rule: on a standard die opposite faces sum to 7 (1-6, 2-5, 3-4); adjacent faces never sum to 7.

Sri Lanka's executive president is both head of state and head of government; the term of office is five years.

The Sri Lankan Parliament has 225 members: 196 elected by district proportional representation and 29 from the national list.

Sri Lanka's official languages under the 13th Amendment framework are Sinhala and Tamil, with English as the link language.

The United Nations has 193 member states; the Security Council has 5 permanent and 10 elected members serving two-year terms.

Nobel Prizes are awarded in Physics, Chemistry, Medicine, Literature, Peace, and Economic Sciences; the Peace Prize is awarded in Oslo, the others in Stockholm.

SAARC has eight member states: Afghanistan, Bangladesh, Bhutan, India, Maldives, Nepal, Pakistan, and Sri Lanka; its secretariat is in Kathmandu.

The Commonwealth is a voluntary association of 56 member states, most of which were formerly part of the British Empire.

World Heritage sites in Sri Lanka include the Sacred City of Anuradhapura, Sigiriya, Polonnaruwa, Galle Fort, Kandy, and the Sinharaja Forest Reserve.

Current-affairs questions should be answered from the date stated in the question; undated 'current' claims are unreliable and should be flagged.

Rate problems with two workers: combined rate = sum of individual rates; time together = 1/(r1 + r2).

Crossing/ferry puzzles: the boatman's return trips count as extra crossings; total crossings for n people with capacity c is 2n - 1 when c = 2.

Weighing puzzles: with a balance and k weighings, at most 3^k outcomes exist, so up to (3^k - 1)/2 suspect coins can be resolved when one is known heavier or lighter.

Water-jug problems: reach the target by repeatedly filling the smaller jug and pouring into the larger, emptying when full; the target must be a multiple of the gcd of jug sizes.

Calendar: a non-leap year shifts the weekday by 1, a leap year by 2; 100 years shift by 5, 400 years by 0.

Clock hands coincide 11 times in 12 hours; they are opposite 11 times in 12 hours; they overlap every 65 5/11 minutes.

Decision tables: enumerate options against criteria, eliminate any option that violates a stated constraint, then rank the survivors.

Data sufficiency: the question asks whether the data is enough, not for the value; test each statement alone before combining.