Analogy; Classification / Odd One Out; Coding and Decoding

Analogy

1.1 What is Analogy?

Analogy means finding a similar relationship. If A relates to B in a certain way, then C relates to D in the same way.

A : B :: C : D

Read as: "A is to B as C is to D"

1.2 Types of Analogies

Type 1: Object and Action / Function

• Pen : Write :: Knife : Cut (object → its function)
• Pencil : Draw :: Scissor : Cut
• Key : Lock :: Switch : Light

Type 2: Object and Material

• Shoe : Leather :: Tyre : Rubber
• Glass : Sand :: Paper : Pulp
• Shirt : Cotton :: Tire : Rubber

Type 3: Individual and Group/Collection

• Fish : School :: Birds : Flock
• Lion : Pride :: Sheep : Flock
• Bees : Swarm :: Ants : Colony

Type 4: Object and Its Place

• Library : Books :: Museum : Antiques
• Student : School :: Customer : Shop
• Patient : Hospital :: Prisoner : Jail

Type 5: Symbol/Representation

• Pigeon : Peace :: White Flag : Surrender
• Dove : Peace :: Lion : Strength
• Red Cross : Medical Aid :: Green : Environment

Type 6: Worker and Tool

• Carpenter : Saw :: Barber : Scissors/Razor
• Farmer : Plough :: Carpenter : Saw
• Painter : Brush :: Sculptor : Chisel

Type 7: Animal and Dwelling

• Lion : Den :: Fox : Burrow
• Dog : Kennel :: Eagle : Eyrie
• Horse : Stable :: Cow : Barn
• Bee : Hive :: Ant : Anthill

Type 8: Animal and Sound

• Dog : Bark :: Cat : Meow
• Lion : Roar :: Cow : Moo
• Frog : Croak :: Snake : Hiss
• Donkey : Bray :: Duck : Quack

Type 9: Object and Related Item

• Elephant : Howdah :: Horse : Saddle
  • (Howdah = seat on elephant's back; Saddle = seat on horse's back)
• Planet : Orbit :: Projectile : Trajectory
• Sphere : Circle :: Cuboid : Rectangle (cross-section/face shape)

Type 10: Science / Subject and Instrument

• Temperature : Thermometer :: Blood pressure : Sphygmomanometer
• Sound : Decibel :: Distance : Meter
• Astronomy : Stars :: Geology : Rocks
• Entomology : Insects :: Ornithology : Birds

1.3 Approach to Analogy Questions

Step 1: Identify the relationship between the first pair (A:B) Step 2: Apply the SAME relationship to find the answer for (C:?) Step 3: Make sure the relationship category matches exactly (not just loosely)

Key Relationships to Remember:

1.4 Important Animal Facts for Analogy

Classification / Odd One Out

2.1 Concept

Find the item that does NOT belong to the same group as others.

2.2 Types

Type 1: Different Category

• Dog, Cat, Cow, Eagle (Eagle is a bird; others are mammals)

Type 2: Different Property

• 17, 23, 37, 21 (21 = 3×7 is composite; others are prime)

Type 3: Different Relationship

• 3:27, 4:64, 5:125, 6:46 (others are perfect cubes; 6³ = 216 ≠ 46)

Type 4: Alphabetical Pattern

• ABCD, EFGH, IJKM, MNOP (IJKM skips L; should be IJKL)

2.3 Strategy

1. Find what the majority has in common
2. Identify what makes one item different
3. The "odd" one must differ from others in a systematic, not random, way

Common Odd-One-Out Tricks

• Among numbers: check if one is prime vs composite, perfect square, odd vs even
• Among words: check if one belongs to different semantic field
• Among letter groups: check if one has different number of vowels, consonants or pattern

Coding and Decoding

3.1 Letter Position in Alphabet

Memory Tricks:

• EJOTY = 5, 10, 15, 20, 25 (every 5th letter)
• Reverse position of A = Z (26), B = Y (25), etc.

3.2 Types of Coding

Type 1: Letter Shifting

• Forward shift: A→D (shift of 3), B→E, etc.
• Backward shift: Z→W, Y→X, etc.

Example: If COME = FRPH (shift of +3):

• C(3)→F(6), O(15)→R(18), M(13)→P(16), E(5)→H(8) ✓

Type 2: Reverse Coding

• A↔Z, B↔Y, C↔X, D↔W, etc. (alphabetical mirror)
• Position reversal: letter at position p → letter at position (27-p)

Type 3: Number Coding

• Letters coded as numbers based on position or some formula
• Example: BOOK = 2+15+15+11 = 43 (sum of positions)
• Alternatively: BOOK → 2, 15, 15, 11 (direct position mapping)

Formula codes:

• BOOK coded as 32, FLOWER as 128 → pattern: 2^(number of letters + 1)
  • BOOK (4 letters) = 2^(4+1) = 2^5 = 32 ✓
  • FLOWER (6 letters) = 2^(6+1) = 2^7 = 128 ✓
  • KEYBOARD (8 letters) = 2^9 = 512

Type 4: Symbol Substitution

• Letters replaced by symbols (+, -, *, @, ...)
• Identify the pattern from given examples

Type 5: Word/Sentence Coding

• Specific words in a sentence are coded as given words
• Identify which code corresponds to which word by cross-referencing two coded sentences

Approach for sentence coding:

1. Compare two coded sentences
2. Find common words in original sentences → corresponding codes
3. By elimination, find code for target word

Type 6: Mixed Coding

• Combination of shifting, reversal and position tricks
• Always check: forward shift, backward shift, position number, skip alternate letters

3.3 Important Patterns

Opposite Letter Pairs: A↔Z, B↔Y, C↔X, D↔W, E↔V, F↔U, G↔T, H↔S, I↔R, J↔Q, K↔P, L↔O, M↔N

Skip Alternate Letters:

• A, C, E, G, I, K, M, O, Q, S, U, W, Y (odd positions)
• B, D, F, H, J, L, N, P, R, T, V, X, Z (even positions)