Number Series
A number series presents a sequence of numbers that follow a consistent rule — a constant difference, a multiplying factor, a repeating operation, or a recognizable family like squares or cubes. Solving it means identifying that rule from the given terms and applying it once more.
Common patterns
- Constant difference or ratio between consecutive terms
- A difference that itself changes by a fixed amount
- Doubling, halving, or another fixed multiplier
- Perfect squares, cubes, or other number families
- A "double and add" or similar two-step recurrence
Worked example
Question: 3, 7, 15, 31, ?
Answer: 63
Each term is double the previous number plus 1.
How to approach Number Series
Identify the information given, test the simplest consistent rule, and verify that your rule explains every relevant part before answering.