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Sentence Codes, Conditional Symbol Codes and Coded Relations

By ExamAtlas · 10/9/2026

Sentence Codes, Conditional Symbol Codes and Coded Relations

Not every code changes letters. In sentence codes each word gets a code word, and you find it by comparing sentences that share words. Conditional codes turn digits or symbols into letters by a table plus rules. Substitution codes rename objects, and coded relations use symbols for family links.

1. Methods Box

TypeMethod
Sentence codes ("sky is blue" = "ka la ma")A word common to two sentences has the code common to both
Conditional table codesCode each digit from the table, then check the conditions in the order given; apply only the first condition that fits unless told otherwise
Substitution ("sky is called sea")Find the real answer first, then give the name it is called by
Coded relations (A + B means A is the father of B)Translate symbol by symbol into a family tree, then read off the asked link

In sentence codes, the order of code words is usually jumbled: never match by position

In substitution codes, answer with the substituted name, not the real one

✗ If red means white and white means black, milk is white  |  ✓ Milk is really white, and white is called black: the answer is black

✗ "tea is hot" = "ri mo sa", so tea = ri by position  |  ✓ Codes are jumbled; eliminate common words first

हिंदी नोट: वाक्य कूट में दो वाक्यों में समान शब्द का कोड भी समान होता है; कोड का क्रम मायने नहीं रखता। "X को Y कहते हैं" वाले प्रश्न में पहले असली उत्तर निकालिए, फिर उसका नया नाम लिखिए।

Exam Pointer: Verified NTPC patterns: sentence codes with a common word (June 2025 Graduate CBT-1), conditional number-and-symbol codes from a table (June 2025 Graduate CBT-1) and symbols coding family relations (June 2025 Graduate CBT-1). Substitution codes had no verified NTPC shift and are tagged syllabus-based.

Pariksha Pattern: Every Way NTPC Asks This Topic

Pattern 1: Sentence codes with common words

[PYQ: NTPC Graduate CBT-1 9-Jun-2025 Shift-3]

EXAM LEVEL

Q. "red rose" is coded "ka ma" and "red ink" is coded "ma pa". What is the code for "rose"?

"red" is common to both and "ma" is common to both codes, so red = ma and rose = ka.

Answer: ka

EXAMATLAS LEVEL

Q. "tea is hot" = "ri mo sa", "hot milk" = "sa ku" and "milk is white" = "ku mo pe". Find the codes for "tea" and "white".

hot = sa (sentences 1 and 2), milk = ku (sentences 2 and 3), is = mo (sentences 1 and 3). So tea = ri and white = pe.

Answer: tea = ri, white = pe

Pattern 2: Conditional codes from a table

[PYQ: NTPC Graduate CBT-1 10-Jun-2025 Shift-3]

Digit codes for both questions:

Digit23456789
CodeKMPRTWBD

Conditions: (i) if the first digit is even and the last digit is odd, their codes are interchanged; (ii) if the first and last digits are both odd, both are coded as Z.

EXAM LEVEL

Q. Code 4837.

Plain codes P B M W. The first digit 4 is even and the last 7 is odd, so interchange the first and last codes: W B M P.

Answer: WBMP

EXAMATLAS LEVEL

Q. Code 9356 and 7325.

9356: first odd, last even, so no condition applies: D M R T. 7325: first and last are odd, so both become Z: Z M K Z.

Answer: DMRT and ZMKZ

Pattern 3: Substitution codes

[Pattern: syllabus-based, PYQ-style]

EXAM LEVEL

Q. If sky is called sea, sea is called water and water is called air, where do fish live?

Fish live in water, and water is called air.

Answer: Air

EXAMATLAS LEVEL

Q. If red means white, white means black, black means yellow and yellow means green, what is the colour of milk and of human blood?

Milk is white, which is called black. Blood is red, which is called white.

Answer: Black; white

Pattern 4: Coded relations

[PYQ: NTPC Graduate CBT-1 12-Jun-2025 Shift-1]

Codes for both questions: A + B means A is the father of B; A − B means A is the sister of B; A × B means A is the brother of B; A ÷ B means A is the mother of B.

EXAM LEVEL

Q. If P + Q − R, how is P related to R?

P is Q's father and Q is R's sister, so Q and R are siblings and P is R's father.

Answer: Father

EXAMATLAS LEVEL

Q. If M ÷ N × O − Q + R, how is M related to R, and how is Q related to M?

M is N's mother; N is O's brother; O is Q's sister; Q is R's father. So N, O and Q are siblings and all M's children, and Q is a male (a father). R is Q's child, so M is R's grandmother, and Q is M's son.

Answer: Grandmother; son

60-Second Revision

  • Sentence codes: match common words to common codes; ignore order.
  • Table codes: code plainly, then apply the conditions exactly as stated.
  • Substitution: real answer first, then its new name.
  • Coded relations: build the tree symbol by symbol; note genders.

Next Step: Coding-Decoding done. Solve a coding set in the ExamAtlas RRB NTPC 2026 mock tests; write positions under the letters and the rule shows in seconds.

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