Number Series — Crack the Pattern
✨ IN SHORT — THE WHOLE LESSON IN 20 SECONDS
A number series is just a hidden rule. First check differences, then multiplication, then squares/cubes. 90% of exam series use only these three ideas.
1. Step One — See the Difference
Subtract each pair: 2, 5, 8, 11, ? Differences are 3, 3, 3 — so next is 11+3 = 14. If differences themselves grow in a pattern (2, 4, 6, 8…), follow that second pattern.
📌 3, 7, 13, 21, ? Differences: 4, 6, 8 → next difference 10 → 31.
2. Step Two — Multiplication Pattern
If numbers grow fast, think ×. 3, 6, 12, 24 → ×2 each time. Mixed patterns like ×2+1 are very common: 2, 5, 11, 23 (×2+1) → next 47.
💡 Trick: Growth slow = add. Growth fast = multiply. Numbers exploding = squares/cubes. Decide in 3 seconds!
3. Step Three — Squares & Cubes
Memorise squares to 20 (1,4,9…400) and cubes to 10 (1,8,27…1000). Series often hide ±1: 2, 10, 30, 68 = 1³+1, 2³+2… watch carefully: 1+1=2, 8+2=10, 27+3=30, 64+4=68.
📌 0, 3, 8, 15, 24 → these are 1²−1, 2²−1, 3²−1, 4²−1, 5²−1 → next 6²−1 = 35.
⚡ Now Practise — 10 Questions
Tap an answer. Right or wrong, we explain why instantly. Learn from every tap!
Q1. 2, 6, 12, 20, 30, ?
Q2. 5, 10, 20, 40, ?
Q3. 1, 4, 9, 16, 25, ?
Q4. 3, 7, 13, 21, 31, ?
Q5. 2, 3, 5, 8, 13, ?
Q6. 100, 90, 81, 73, 66, ?
Q7. 4, 9, 19, 39, ?
Q8. 7, 14, 28, 56, ?
Q9. 1, 8, 27, 64, ?
Q10. 90, 80, 71, 63, 56, ?
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