Reasoning – Number Series
What is Number Series?
Identify the next or missing number in a sequence governed by a mathematical pattern.
Common Patterns
1. Arithmetic (+/− constant)
2. Geometric (×/÷)
3. Square/Cube Numbers
4. Prime numbers
5. Mixed or alternating series
Example Questions
- Series: 2, 4, 8, 16, ?
Answer: Answer: 32 (×2 each step)
- Series: 1, 4, 9, 16, ?
Answer: Answer: 25 (Perfect squares)
Exam Tips
- Write differences between terms to spot progression.
- Look for alternating or two-part sequences.
- Test with squares, cubes, or common primes.
Common Mistakes
- Assuming a single step pattern prematurely.
- Skipping check for alternating or position-based changes.
- Missing mix of operations (e.g., +2, ×2 alternately).
Quick Revision Checklist
- Memorize square/cube numbers up to 20.
- Practice both missing term and wrong term series.
- Use pen-and-paper to plot differences.
Summary: Number Series problems improve analytical and predictive skills. Consistent practice with varied series ensures strong pattern recognition.