Example 1 — Block staircase
EasyProblem
A staircase has 2, 5, 8, 11 blocks per step. How many blocks in the 6th step?
Solution
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Terms increase by a constant amount, so it's an additive growing pattern.
Name the structure before touching arithmetic — that is what makes the right method obvious.
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Ask the recognition question: Is the change between consecutive terms a constant amount or a constant factor?
If the answer is yes, the concept applies; the cue, not a keyword, decides the method.
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Find the rule: each step adds 3, so , .
The rule is chosen only after the structure matches, so the steps mean something.
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Keep units, shape, or answer form tied to the story so the work does not become symbol pushing.
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Check the answer against the original question.
It should fit the mental model — same step (or factor) every term. If it does not, revisit the recognition step before changing the arithmetic.
Answer
17 blocks
Takeaway: A constant step lets you jump to any term with .