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Lesson 340 min read

Analytical Ability

Logic, Syllogisms, Venn Diagrams & Pattern Recognition (30% of exam)

Syllogisms

A syllogism is a logical argument with three parts: two premises and a conclusion.

Structure

  • Major Premise: A general statement
  • Minor Premise: A specific statement
  • Conclusion: Logically follows from both premises

Example:

All Filipinos are Asians. (Major Premise)

Juan is a Filipino. (Minor Premise)

Therefore, Juan is an Asian. (Conclusion)

Valid Syllogism

All dogs are animals.

Buddy is a dog.

∴ Buddy is an animal. ✓

Invalid Syllogism

All dogs are animals.

Buddy is an animal.

∴ Buddy is a dog. ✗

Venn Diagrams

"All A are B"

Circle A is completely inside Circle B

Example: All doctors are professionals → Doctor circle inside Professional circle

"No A are B"

Circles A and B don't overlap at all

Example: No dogs are cats → Separate circles

"Some A are B"

Circles A and B partially overlap

Example: Some students are athletes → Overlapping circles

"Some A are not B"

Part of circle A is outside circle B

Example: Some birds are not flyers → Some of Bird circle is outside Flyers circle

Coding-Decoding

Common Patterns

  • Letter shifting: Each letter moves by a fixed number (A→B→C)
  • Reverse alphabet: A=Z, B=Y, C=X, D=W...
  • Number substitution: A=1, B=2, C=3...
  • Vowel/Consonant swap: Different rules for vowels and consonants

Example:

If CAT = DBU, then DOG = ?

Pattern: Each letter shifts +1 (C→D, A→B, T→U)

Answer: EPH (D→E, O→P, G→H)

Example (Reverse):

If BAD = YZW, then GOOD = ?

Pattern: Each letter is its reverse (A=Z, B=Y, C=X...)

Answer: TLLW (G=T, O=L, O=L, D=W)

Pattern Recognition Tips

1

Look for differences - What changes between each item?

2

Check for rotation - Is the pattern rotating clockwise or counterclockwise?

3

Count elements - Are shapes being added or removed?

4

Identify symmetry - Is there mirror or rotational symmetry?

5

Check color changes - Are colors alternating or following a sequence?