Coding-Decoding & Blood Relations: Crack the Code, Draw the Tree

Q: Pointing to a man, a woman said, 'His mother is the only daughter of my mother.' How is the woman related to the man?

'The only daughter of my mother' must be the woman herself, since she is her mother's single daughter. So the man's mother IS the woman — therefore the woman is the man's mother.

A from-scratch, exam-focused guide to bank-prelims Coding-Decoding (letter, number and new-pattern sentence coding) and Blood Relations. Learn the EJOTY and opposite-letter shortcuts, a clean method for sentence coding, and the draw-the-family-tree technique — with fully worked, verified examples tuned to tight sectional timing and 0.25 negative marking.

By the PadhoDost Team · 📖 8 min read · Updated 4 August 2026

Part of Banking (IBPS / SBI) prep

🧠 The secret chit-language of school

Remember passing chits in class where 'library' secretly meant 'the boring lecture' and 'chai' meant 'let's bunk'? You and your friend agreed on a rule, and suddenly one ordinary word carried a hidden meaning. Coding-Decoding is exactly that game — the examiner fixes a secret rule, and your only job is to spot the rule and reverse it. Blood Relations is the same idea with people: a tangled sentence is really a simple family tree wearing a disguise. Padho, dost — once you learn to decode and to draw, these become your fastest, surest marks.

In IBPS and SBI Prelims, the Reasoning section is short and brutal: roughly 35 questions in 20 minutes, with 0.25 negative marking for every wrong answer. Coding-Decoding and Blood Relations are gold here because a well-practised student cracks them in under a minute with near-perfect accuracy — no lengthy calculation, just a rule and a diagram. Skip the guesswork; a blind attempt here costs you a quarter mark AND precious seconds.

Part 1: Coding-Decoding Basics

Most coding rests on one skill: knowing the position of a letter in the alphabet (A=1 ... Z=26) and its reverse position counted from the back (Z=1 ... A=26). The common rules you will see are: shift a letter forward or backward by a fixed number, replace a letter with its opposite (A with Z, B with Y), or use position-number tricks. Memorise the anchor letters and these jumps become instant.

Letter	Position	Reverse (27 − pos)	Opposite letter
A	1	26	Z
E	5	22	V
J	10	17	Q
O	15	12	L
T	20	7	G
Y	25	2	B

💡 Learn the 'EJOTY' anchors — E=5, J=10, O=15, T=20, Y=25. To find any letter's number, jump to the nearest anchor and count a step or two. For opposite letters, use the rule Opposite = 27 − Position (so P=16 pairs with K=11, since 27 − 16 = 11). These two shortcuts alone cover the bulk of coding questions.

📝 Worked example: letter-shift coding

Question: In a code, TIGER is written as UJHFS. How is LION written?

Step 1 — Compare TIGER with UJHFS letter by letter: T→U, I→J, G→H, E→F, R→S.

Step 2 — Spot the rule: every letter moves +1 (one step forward).

Step 3 — Apply the same rule to LION: L→M, I→J, O→P, N→O.

Answer: LION is written as MJPO.

New-Pattern (Sentence) Coding

Modern bank exams love 'sentence coding', where whole phrases are coded and you must find the code for one word. There is no letter-shift here — you match words across sentences. It looks scary but follows one clean idea: whatever word is common to two sentences must share the code that is common to those same two sentences.

Method for new-pattern coding

1Write each sentence and its code neatly, one below the other.
2Find a word that appears in two sentences; the code common to those two sentences stands for that word.
3Find a code that repeats across ALL sentences — it belongs to the word that repeats across all.
4Cancel the pairs you have confirmed to squeeze out the remaining words.
5Cross-check that every sentence maps fully before you tick the answer.

📝 Worked example: sentence coding

'pen is blue' = 'ta na sa'

'blue is sky' = 'na ra ta'

'sky is high' = 'ra na pa'

Step 1 — 'na' appears in all three codes, and 'is' is the only word common to all three sentences, so is = na.

Step 2 — Sentences 1 and 2 share the words 'is' and 'blue' and the codes 'na' and 'ta'. Since is = na, the leftover gives blue = ta.

Step 3 — Sentences 2 and 3 share 'is' and 'sky' and the codes 'na' and 'ra'. Since is = na, sky = ra.

Answer: the code for 'blue' is ta. (Check: pen = sa, high = pa — every sentence now maps cleanly.)

Part 2: Blood Relations

A blood-relation question is a story that hides a family tree. Your winning move is to STOP reading it as English and start drawing it as a diagram. Once the tree is on paper, the answer simply reads off it.

Family-tree drawing rules

✓Show a male as a square and a female as a circle — fix a person's gender only when the sentence actually tells you.
✓Use a vertical line to link different generations (parent above, child below).
✓Use a horizontal line for the same generation (brother — sister, husband — wife).
✓Replace tricky phrases like 'the only daughter of my mother' with the actual person before moving on.
✓Always read the final relation FROM the tree, never from memory.

📝 Worked example: pointing-type relation

Question: Pointing to a photograph, Rekha said, 'She is the daughter of my grandfather's only son.'

Step 1 — Rekha's grandfather has only one son, and Rekha is his descendant, so that only son is Rekha's own father.

Step 2 — 'Daughter of Rekha's father' is therefore Rekha herself OR her sister.

Step 3 — Rekha is pointing at someone else in the photo ('She'), so it cannot be Rekha.

Answer: The girl in the photo is Rekha's sister.

⚠️ The biggest trap is assuming gender from a name or a role. 'The engineer', 'the doctor', 'my friend' — none of these tells you male or female, so never draw the symbol until the sentence confirms it. A single wrong gender collapses the whole tree and gifts the examiner your 0.25 negative mark.

Exam-day quick revision

✓Memorise EJOTY (5, 10, 15, 20, 25) and the Opposite = 27 − position rule for opposite letters.
✓For sentence coding, hunt for the word and the code that are common to the same two lines.
✓In blood relations, always draw — squares, circles, vertical and horizontal lines.
✓If a question feels tangled after 60–75 seconds, mark it for review and move on; accuracy beats ego.
✓Attempt only when the tree or code is fully clear — a confident 5 beats a shaky 8 under negative marking.

⚡ Quick check

Pointing to a man, a woman said, 'His mother is the only daughter of my mother.' How is the woman related to the man?

Ready to test yourself? 🎯

Lock it in with the practice test for this chapter.

Take the practice test →

Keep studying

8 min read

Puzzles & Seating Arrangement: Build a Grid, Eliminate Cases

7 min read

Syllogism & Inequality: Your Easiest Guaranteed Marks in Bank Prelims

7 min read

Simplification & Approximation: Your Fastest Marks in Bank Prelims

7 min read

Data Interpretation for Bank Exams: Read Any Table, Graph or Caselet Fast

See all Banking (IBPS / SBI) study material →