Prelims · 8 Mental Ability · 8.9 Coding–decoding

8.9.2 Number, substitution and sentence (word-to-code) coding

Number codes turn letters into values (positions, sums, products), substitution codes rename objects, and sentence codes hide each word behind a code word that you isolate by comparing sentences that share words.

  • APPSC Group 2 · Prelims
  • Standard level
  • 8 min read
  • Full course

Key terms

  • number coding
  • position values
  • sum of letters
  • product of letters
  • reverse values
  • letter-digit table
  • substitution coding
  • sentence coding
  • common words method
  • digit sentence codes
  • conditional coding
  • digit coding
  • odd and even places

What this note covers

  1. Core factsFoundation
  2. ExplainedStandard
  3. DeeperAdvanced
  4. Common trapsFoundation
  5. Quick revisionFoundation

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