C7
Grid Path Counting
网格路径计数
Counting / 计数Grades G4 - G7
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What It Looks Like
Recognition signals — when you see these, think of this structure:
- 1A grid or lattice
- 2Movement restricted to certain directions (right/up)
- 3Going from one corner to another
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What It Really Tests
The core mathematical idea behind this structure:
Count valid paths on a grid under specific movement rules.
在特定移动规则下, 计算网格上的有效路径数。
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Why Students Get Stuck
Common mistakes to watch out for:
- ⚠Guessing path count by visual inspection
- ⚠Forgetting a movement restriction
- ⚠Missing the recursive/additive structure
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Your First Step
How to begin thinking about problems with this structure:
Start with a small grid, label each intersection with its path count, and build up.
从小网格开始, 在每个交叉点标记路径数, 逐步推广。
Related Structures
These structures share similar patterns or thinking approaches: