1 General Mental and Psychological Abilities · 1.1.5 Syllogism and verbal reasoning

1.1.5.7 Truth-tellers and liars

Assume one person's type (or one suspect), work out what every statement must then be, and keep only the case with no contradiction; two statements that contradict each other split the true and the false between them.

  • APPSC Group 1
  • Advanced level
  • 8 min read
  • Full course

Key terms

  • truth-teller
  • liar
  • knights and knaves
  • consistency
  • assume and test
  • contradiction pair
  • exactly one statement true
  • exactly one statement false
  • who did it
  • alternator
  • normal person
  • two statements each
  • exactly k liars

What this note covers

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

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