01 Key Concepts
Number Series
A sequence of numbers following a consistent rule, such as adding a fixed amount, multiplying by a factor, or alternating between operations.
Arithmetic Patterns
Each term differs from the previous one by a constant amount (a common difference).
Geometric Patterns
Each term is found by multiplying the previous one by a constant factor (a common ratio).
Letter Series
Sequences of letters following a rule based on their position in the alphabet, such as skipping a fixed number of letters each time.
Combined/Alternating Patterns
Some sequences alternate between two separate rules or interleave two simpler sequences together.
02 Solved Examples
Example 1 Find the next number: 3, 7, 11, 15, ...
- Find the difference between consecutive terms: 7-3=4, 11-7=4, 15-11=4.
- The pattern adds 4 each time.
- Next term: 15+4.
Answer: 19
Example 2 Find the next number: 2, 6, 18, 54, ...
- Find the ratio between consecutive terms: 6/2=3, 18/6=3, 54/18=3.
- The pattern multiplies by 3 each time.
- Next term: 54*3.
Answer: 162
Example 3 Find the next letter: A, C, E, G, ...
- Convert to positions: A=1, C=3, E=5, G=7.
- Each term skips one letter, adding 2 to the position each time.
- Next position: 7+2=9, which is the letter I.
Answer: I
03 Practice Questions
1Find the next number: 5, 10, 15, 20, ...
25
2Find the next number: 1, 3, 9, 27, ...
81
3Find the next number: 100, 90, 80, 70, ...
60
4Find the next letter: B, D, F, H, ...
J
5Find the missing number: 2, 4, 8, __, 32.
16
📄 Pattern Recognition — Downloadable Worksheet
10 questions with a full answer key. Grab the PDF to print, or try the interactive version in your browser.