Analogy & Classification

In number analogy, find the hidden mathematical relation between the first pair, then apply it to the second. Common relations: (1) Square/Cube — 4:16, 5:125; (2) Add/Subtract a constant — 7:11 (+4); (3) Multiply/Divide — 6:36 (x6); (4) n and n+1 operations like 5:30 (5x6). MEMORY AID 'SCADM': Square, Cube, Add, Difference, Multiply — test in this order. For sum-of-digits or reverse-digit types, check 12:21 (reverse) or 23:5 (2+3). Always test the SAME operation on both pairs; if it fails, switch operations. For grouped numbers like (3,9,27), look for GP ratio. Eliminate options by quick mental arithmetic. Watch for 'odd one' framing where one pair breaks the rule.

Convert letters to position numbers (A=1...Z=26). MEMORY AID 'EJOTY': E=5, J=10, O=15, T=20, Y=25 — count forward/back from these milestones to fix any letter fast. Reverse positions: A=26, Z=1 (use 27-position). Common patterns: +1 skip (AB:CD), opposite letters (A-Z, B-Y sum=27 rule), gap series (A_C, skip one). For pairs like AZ:BY, note A+Z and B+Y both pair to position-sum 27. For DH:EI type, each letter +1. Always write the position numbers below letters to expose the gap. Backward alphabet (Z,Y,X...) is favourite in SI papers — practise reciting reverse alphabet.

Q: 7 : 56 :: 9 : ? Solve: 7x8=56, so relation is nx(n+1). Apply: 9x10=90. Answer 90. Q: BD : FH :: JL : ? Positions B=2,D=4,F=6,H=8 — each pair is consecutive even letters increasing by 4 (B->F is +4, D->H is +4). Next: J=10,L=12, add 4 -> N=14, P=16, so NP. Q: 25:36 :: 49:? These are squares 5^2,6^2 then 7^2, so next 8^2=64. SHORTCUT: when both numbers are perfect squares of consecutive integers, the answer is the next perfect square. Verify by checking the difference pattern (11,13,... odd-number gaps confirm squares).

Word analogy tests logical bonds between words. Master these standard types: (1) Worker:Tool — Carpenter:Saw; (2) Worker:Product — Author:Book; (3) Cause:Effect — Spark:Fire; (4) Synonym — Big:Large; (5) Antonym — Hot:Cold; (6) Part:Whole — Petal:Flower; (7) Animal:Young — Cow:Calf; (8) Animal:Home — Bee:Hive; (9) Instrument:Measurement — Thermometer:Temperature; (10) Country:Currency — Japan:Yen. TECHNIQUE: form a clear SENTENCE linking the first pair ('A carpenter uses a saw'), then plug the options into the same sentence — only one fits exactly. Keep word order identical; if A:B is tool:worker, the answer must also be tool:worker, not reversed.

The fastest reliable method is the 'bridge sentence'. For Doctor:Hospital, say 'A doctor works in a hospital.' For the option Teacher:?, the answer must be the place a teacher works — School. If two options seem to fit, make the bridge MORE specific to break the tie (add 'primarily', 'is made of', 'cures'). MEMORY AID: KEEP DIRECTION FIXED — read whether the relation goes object->place or place->object and preserve it. Beware near-traps: for Pen:Write, the link is 'used to', so Knife:Cut, not Knife:Sharp. Eliminate options that reverse the relationship even if topically related. Strong vocabulary on professions, animals, geography and tools boosts speed.

Q: Pride : Lions :: ? : Wolves. Bridge: 'A pride is a group of lions.' A group of wolves is a Pack. Answer: Pack. Q: Optimist : Cheerful :: Pessimist : ? Bridge: an optimist is characterised by being cheerful; a pessimist is characterised by being Gloomy. Answer: Gloomy. Q: Painter : Brush :: Blacksmith : ? Bridge: a painter works with a brush (his tool); a blacksmith works with a Hammer. Answer: Hammer. NOTE the trap option 'Iron' — iron is the material, not the tool, so the direction breaks. Always confirm the option matches the EXACT role (tool, product, place) established by the first pair.

Classification (Odd-One-Out / 'choose the different one') asks you to spot the item NOT sharing the common property of the rest. Categories tested: (1) Living/non-living groups — animals, birds, flowers; (2) Mathematical properties — primes, perfect squares, even/odd, multiples; (3) Letter patterns — consonant clusters, vowel positions, equal gaps; (4) Word meaning groups — metals, instruments, professions. METHOD: identify the rule that 3 of 4 options obey, then the rejected one is the answer. MEMORY AID 'PAGE': Primes/squares, Alphabet-gap, Group/category, Even-odd — scan these checks quickly. Beware double-traps where two options seem odd; pick the one breaking the MOST fundamental rule.

For number classification, run a fixed checklist: (1) Are most PRIME (2,3,5,7,11...)? then the composite is odd. (2) Perfect SQUARES (4,9,16,25)? (3) Perfect CUBES (8,27,64)? (4) All EVEN or all ODD except one? (5) MULTIPLES of a number (15,30,45)? (6) Digit-sum or digit-reverse pattern? SHORTCUT: 1 is NEITHER prime nor composite — a classic trap. 2 is the ONLY even prime. For pairs like (8,27,64,100): 8,27,64 are cubes but 100 is a square, so 100 is odd. Always test the simplest rule first (even/odd) before complex ones. Confirm by ensuring exactly THREE share the property.

Q: (a) Rose (b) Lotus (c) Marigold (d) Mango. Three are flowers; Mango is a fruit -> answer (d). Q: (a) 8 (b) 27 (c) 64 (d) 81. 8=2^3, 27=3^3, 64=4^3 are cubes; 81=3^4 (or 9^2) is not a cube -> answer (d). Q: (a) BD (b) FH (c) JM (d) PR. Gaps: B-D=1 skip, F-H=1 skip, P-R=1 skip, but J-M has 2 letters skipped (J,K,L,M) -> JM is odd, answer (c). TIP: when 3 options have an equal alphabet gap, the one with a different gap is the misfit. Always count gaps using position numbers to avoid careless errors.

This variant gives a stated pair and asks which OPTION PAIR shares the same relationship. Steps: (1) Define the precise relation of the given pair as a bridge sentence. (2) Note the DIRECTION (A causes B, A is part of B, etc.). (3) Test each option pair against the SAME bridge; the matching one wins. MEMORY AID 'DBR': Define-Bridge-Reject. Watch for reversed pairs — if given is Tool:Worker, a Worker:Tool option is wrong even if related. Also check the LEVEL of relation: Synonym vs near-synonym, whole-part vs part-part. If two options pass, tighten the bridge (degree, material, function). Eliminate distractors that are merely 'same category' but lack the specific link.

Examiners plant three trap styles: (1) REVERSED direction — same words, wrong order; (2) SAME CATEGORY but different relation (e.g., Dog:Bark given, trap Cat:Animal vs correct Cat:Mew); (3) PARTIAL match where only one word fits the theme. TIE-BREAK rule: make the bridge as specific as the original. For Caterpillar:Butterfly (life-stage transformation), choose Tadpole:Frog, NOT Egg:Hen (egg isn't a larval stage of the same creature pattern equally, but tadpole->frog is the cleanest metamorphosis). SHORTCUT: degree analogies (Warm:Hot = Cool:Cold) must keep intensity order. Always re-read both option words; careless single-word matching causes most errors here.

Q: 'Doctor : Stethoscope' — choose the analogous pair. Bridge: a doctor uses a stethoscope as a professional tool. Options: (a) Farmer:Plough (b) Singer:Song (c) Student:School. Farmer:Plough matches (worker:tool) -> answer (a); Singer:Song is worker:product, School is workplace, both wrong direction/relation. Q: 'Day : Night' (opposites) — choose: (a) Sun:Moon (b) Up:Down (c) Cat:Dog. Up:Down are direct antonyms -> answer (b). Sun and Moon are related objects, not opposites. ALWAYS restate the bridge for each candidate; the option that fits word-for-word in the same sentence is correct.