Reasoning Methods

Reasoning Methods

Reasoning rewards pattern recognition. Use fixed methods.

Number series

Check in this order:

  1. Difference
  2. Difference of difference
  3. Multiplication/division
  4. Squares/cubes
  5. Alternating pattern
  6. Prime/fibonacci pattern

Example:

2, 6, 12, 20, 30, ?

Differences:

4, 6, 8, 10

Next difference = 12, answer = 42.

Letter series

Convert letters to positions:

A=1, B=2, C=3, ..., Z=26

Check:

  • forward shift,
  • backward shift,
  • alternating shift,
  • reverse alphabet pair: A-Z, B-Y.

Coding-decoding

Common rules:

  • Shift letters: A→C means +2
  • Reverse alphabet: A↔Z, B↔Y
  • Position values: CAT = 3,1,20
  • Mixed letter-number coding
  • Word reversal

Method:

  1. Compare known word and code.
  2. Identify operation.
  3. Apply exactly.

Blood relations

Never solve in text. Draw.

Symbols:

M = male
F = female
↑ parent
↓ child
— spouse/sibling depending context

Common relation codes:

  • mother’s brother = maternal uncle
  • father’s sister = paternal aunt
  • wife’s mother = mother-in-law
  • husband’s father = father-in-law

Direction sense

Draw arrows.

Use coordinate method:

  • North = +y
  • South = -y
  • East = +x
  • West = -x

Distance from origin:

sqrt(x² + y²)

if diagonal is required.

Syllogism

Use Venn diagrams.

Important:

  • “All A are B” does not mean all B are A.
  • “Some A are B” means at least one overlap.
  • “No A is B” means no overlap.
  • Conclusions must definitely follow, not possibly follow.

Statement and conclusion

Answer only what follows logically.

Do not use:

  • personal belief,
  • outside knowledge,
  • emotional assumptions.

Data sufficiency

You do not need to find the answer. You need to decide whether the data is enough.

Check:

  • statement I alone,
  • statement II alone,
  • both together,
  • neither.

Visual reasoning

Check:

  • rotation,
  • mirror image,
  • number of sides,
  • number of dots/lines,
  • shading position,
  • clockwise movement,
  • alternating shapes.

Logical puzzles

Method:

  1. Draw table.
  2. Put fixed information first.
  3. Use negative information carefully.
  4. Do not infer unless forced.