CSS Prepare

mpt · CSS study notes

Grouping & Classification

Core Idea

Sort items into categories based on a shared rule, or spot the item that doesn't belong (odd one out). The key skill is identifying WHAT property connects the majority of the group.

Common Classification Bases

  • Category/type: all items belong to the same broader class (e.g., all fruits, all tools)
  • Function/use: items serve the same purpose
  • Property/attribute: shared physical or abstract trait (color, shape, count, spelling pattern)
  • Relationship pattern: items follow the same internal structure (e.g., all are anagram pairs, all have double letters)

Strategy

  1. Look at all items first — don't lock onto the first pattern you notice
  2. Test the most obvious category (type/class) first, then move to structural patterns if that fails
  3. For "odd one out": find what 3 (or more) items share, then confirm the remaining one truly lacks that property
  4. Be wary of multiple valid-looking patterns — pick the one that cleanly explains ALL but one item

Worked Examples

  1. Which does not belong: Apple, Banana, Carrot, Mango → Apple/Banana/Mango are fruits, Carrot is a vegetable → Carrot
  2. Which does not belong: Triangle, Square, Circle, Cube → first three are 2D shapes, Cube is 3D → Cube
  3. Which does not belong: Dog, Cat, Lion, Snake → first three are mammals, Snake is a reptile → Snake
  4. Which does not belong: 4, 9, 16, 20, 25 → 4,9,16,25 are perfect squares, 20 is not → 20
  5. Which does not belong: CDE, FGH, JKL, MNP → first three are consecutive letter triplets, MNP skips a letter (should be MNO) → MNP

Drill

  1. Odd one out: Piano, Guitar, Violin, Flute — Flute (others are string instruments)
  2. Odd one out: 121, 144, 169, 200 — 200 (others are perfect squares)
  3. Odd one out: London, Paris, Tokyo, Africa — Africa (a continent, not a city)
  4. Odd one out: Sun, Moon, Earth, Star — Moon (others emit their own light/are broader categories; Moon reflects light)
  5. Odd one out: ABC, DEF, GHI, JKM — JKM (breaks the consecutive-triplet pattern)

Practice tracker

YYYY-MM-DD

  • Attempted/Correct:
  • Mistake pattern: