Classification (Odd One Out)

Finding the item that doesn't share the group's common property — testing precise categorisation, not just surface similarity.

📖 ~4 min read 🧠 RRB NTPC / Group D — Reasoning

Check the most obvious category first (all animals, all fruits) — then narrow to a more specific shared trait if all items pass the broad check
For number sets: test odd/even, prime/composite, perfect square, multiples
For word sets: check spelling pattern, letter count, or a common prefix/suffix rather than just meaning

💡 Example: 8, 27, 64, 125, 150 → 8=2³, 27=3³, 64=4³, 125=5³ (all perfect cubes). 150 is not a cube, so it's the odd one out.

⚠️ Watch for cases where the "obvious" category fits every item — the real distinguishing property is often more specific.

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