Number Series

Quick pattern-spotting for missing and wrong number questions in the reasoning section.

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

Check	What to Look For
1. Constant difference	Same number added/subtracted each step
2. Constant ratio	Same number multiplied/divided each step
3. Difference-of-differences	Differences themselves increase/decrease steadily
4. Squares/cubes	Terms match n², n³, or n²±k patterns
5. Alternating terms	Odd and even positions follow two separate simple rules

💡 Example: 5, 11, 23, 47, ? → each term = previous×2+1. Next = 47×2+1 = 95

💡 For wrong-number questions, spot-check 2-3 consecutive gaps to isolate the break rather than recomputing the whole series.

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