CUET UG General Test Logical Reasoning Coding-Decoding Blood Relations Direction Tests

Must‑Know

• In coding-decoding, if ‘APPLE’ is coded as ‘CRRNG’, each letter shifts by +2 positions in the alphabet; thus, ‘MANGO’ becomes ‘OCPIQ’.
• Reverse alphabet coding: Z = 1, Y = 2, ..., A = 26; so ‘CAT’ becomes (24)(26)(7) = 24267.
• In substitution coding, if ‘red’ is called ‘blue’, ‘blue’ is called ‘green’, then grass (actually green) appears blue under code.
• For blood relations, maternal uncle = mother’s brother; paternal aunt = father’s sister — terms are gender-specific and lineage-defined.
• If A is B’s sister, B is C’s father, then A is C’s paternal aunt — deduced via generational mapping.
• Siblings share the same parents; half-siblings share one parent — distinction matters in relation puzzles.
• In direction tests, clockwise right turn from North leads to East; counterclockwise left turn from South leads to East.
• Pythagorean triplet (3,4,5) used in distance problems: if a person walks 3 km East, then 4 km North, shortest distance = 5 km.
• Relative direction: if P is to the South of Q, then Q is to the North of P — inverse relation must be applied.
• After sunrise, shadow falls West; after sunset, shadow falls East — based on sun’s position.
• At 12 noon, shadow is shortest and points due North (in India, Northern Hemisphere).
• In coded blood relations, if A × B means A is brother of B, A + B means A is mother of B, then M + N × O means M is mother of N, who is brother of O → M is mother of both.
• Midpoint formula in direction sense: if a person moves from (x₁,y₁) to (x₂,y₂), midpoint = ((x₁+x₂)/2, (y₁+y₂)/2) — useful in coordinate-based questions.
• Distance formula: √[(x₂–x₁)² + (y₂–y₁)²] — applied when final position coordinates are known.
• In forward coding, ‘JUMP’ → ‘KVNQ’ uses +1 shift per letter; reverse decoding requires –1 shift.
• If ‘LOVE’ is coded as 47 and ‘HATE’ as 32 using A=1, B=2…Z=26, sum of positions: L(12)+O(15)+V(22)+E(5)=54 → verify from NCERT for exact pattern.
• Generational gap rule: a child cannot be parent to an elder — eliminate impossible relations in puzzles.
• In circular arrangement with blood relations, gender notation (+ for male, – for female) helps track relationships.
• Cardinal directions: North, South, East, West; intercardinal: NE, SE, SW, NW — total 8 directions used in path tracing.
• Right-hand rule in direction: turning right from North → East, left from West → South — consistent with clock motion.

Difficulty Level

Intermediate — because it combines symbolic interpretation, spatial reasoning, and logical deduction, but does not require advanced math or external knowledge beyond basic alphabet and family structures.

Common CUET Traps

• Trap: Assuming "uncle" can only be paternal. Avoid: Consider both maternal (mother’s brother) and paternal (father’s brother) possibilities unless specified.
• Trap: Taking coded messages literally, e.g., thinking ‘blue’ means actual blue color. Avoid: Focus on substitution rules given in the question, not real-world meanings.
• Trap: Ignoring direction sequence — e.g., turning left after moving backward. Avoid: Redraw path step-by-step; track net displacement using vectors or grid.

Practice MCQs

1. If ‘ROSE’ is coded as ‘TQUG’, how is ‘LILY’ coded?
   A) NKNA
   B) NJNZ
   C) MKMZ
   D) NKNA

Answer: A) NKNA
Explanation: Each letter increases by +2: L→N, I→K, L→N, Y→A.
Why others fail: Option B uses +1 for some letters — inconsistent with pattern.

1. Pointing to a man, Priya says, “His mother is the only daughter of my mother.” How is Priya related to the man?
   A) Mother
   B) Sister
   C) Daughter
   D) Aunt

Answer: B) Sister
Explanation: “Only daughter of my mother” = Priya herself → man’s mother is Priya → Priya is mother? No — contradiction. Correct: Priya is sister (same mother).
Why others fail: Misreading “only daughter” as referring to someone else leads to choosing aunt.

1. A man walks 5 km South, turns left and walks 3 km, then turns right and walks 2 km. Where is he now relative to starting point?
   A) South-West
   B) South-East
   C) North-East
   D) North-West

Answer: B) South-East
Explanation: After South, left → East; then right → South again; net: South and East components → South-East.
Why others fail: Forgetting that right turn from East leads to South, not West.

1. If A + B means A is sister of B, A × B means A is son of B, then what does P × Q + R mean?
   A) P is son of Q, who is sister of R
   B) P is nephew of R
   C) P is brother of R
   D) P is son of R

Answer: A) P is son of Q, who is sister of R
Explanation: P × Q = P is son of Q; Q + R = Q is sister of R → Q is female.
Why others fail: Assuming Q is male leads to incorrect relation with R.

1. If ‘MADRAS’ is coded as ‘NBESBT’, how is ‘DELHI’ coded?
   A) EFMIJ
   B) EFMJI
   C) EDLHI
   D) EFMIK

Answer: A) EFMIJ
Explanation: Each letter shifts +1: D→E, E→F, L→M, H→I, I→J → EFMIJ.
Why others fail: Option B reverses last two letters — distractor based on spelling confusion.

Last‑Minute Revision

• ⚠️ Left turn = counterclockwise; right turn = clockwise — always relative to current facing.
• ⚠️ Mother’s or father’s brother = uncle; mother’s or father’s sister = aunt — gender-specific.
• ⚠️ Son of father’s sister = cousin — not uncle.
• ⚠️ A × B = A is brother of B → A is male, B could be male/female.
• ⚠️ In alphabet coding, A=1, Z=26 standard unless specified.
• ⚠️ Shadow direction opposite to sun: morning shadow → West.
• ⚠️ Distance = √(East-West)² + (North-South)² — Pythagoras applies.
• ⚠️ Midpoint: average of x and y coordinates — use in return-path questions.
• ⚠️ “Only son” implies no other male sibling — eliminates alternatives.
• ⚠️ Sister’s daughter = niece — not daughter.
• ⚠️ After 12 PM, shadow moves from North to East — sun shifts West.
• ⚠️ Code “if” often introduces conditional logic — read carefully.
• ⚠️ Reverse alphabet: A=26, B=25…Z=1 — used in some NTA papers.
• ⚠️ Generations: grandparent → parent → child — three levels in many puzzles.
• ⚠️ “Wife of father” = mother — direct synonym in blood relation.
• ⚠️ Clockwise movement: North → East → South → West → North.
• ⚠️ Uncle’s son = cousin — common trap to say nephew.
• ⚠️ “Daughter-in-law” = wife of son — not daughter.
• ⚠️ Use diagramming: draw family tree or direction path — saves time.
• ⚠️ Mnemonic: “Never Eat Soggy Waffles” = North, East, South, West — order of directions.