Finding the Common Difference (Grades 4–5)
In an arithmetic sequence, the gap between consecutive terms is constant — the common difference. Find it by subtracting any term from the one after it. Once you know the difference, you can extend the sequence forward or backward (a negative difference means it decreases).
Understanding finding the common difference
In an arithmetic sequence, the gap between consecutive terms is constant — the common difference. Find it by subtracting any term from the one after it. Once you know the difference, you can extend the sequence forward or backward (a negative difference means it decreases).
Key Idea
In an arithmetic sequence, the gap between consecutive terms is constant — the common difference. Find it by subtracting any term from the one after it. Once you know the difference, you can extend the sequence forward or backward (a negative difference means it decreases).
Seeing it in action
Worked example
Find the common difference and next term: 2, 5, 8, 11, __.
Difference = 5 − 2 = 3. Next = 11 + 3 = 14.
The same gap repeats between terms.
Try a few
10, 7, 4, __ — difference and next?
1, 6, 11, __
20, 24, 28, __
Number Current
A calm number-line game for placing whole numbers and extending patterns.
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