Counting cubes in a stack, including hidden ones

A picture of a stack of cubes hides the ones behind and underneath. Counting layer by layer, or column by column across the base, reaches the cubes you cannot see. The question is usually how many cubes there are, or how many faces are painted.

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LearnWhat it is, how to spot it, a worked example, and where it goes wrong.
Practice — 3-point ladder1 problem. Three in a row finishes it.0/3 in a row · 0/1 solved
Practice — 4-point ladder3 problems. Three in a row finishes it.0/3 in a row · 0/3 solved
Practice — 5-point ladder1 problem. Three in a row finishes it.0/3 in a row · 0/1 solved
Skill quizFinish every ladder that has problems first.Finish the ladders above first

Before and after

Needs first

CNT-04Casework GEO-13Building and counting with unit cubes

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Nothing yet. No other skill in the Atlas lists this one as a prerequisite.

In official papers

No indexed official paper question has been tagged with CNT-14 yet. The index grows one paper at a time, and it records only question numbers, point values and our own skill tags — never the problems themselves.

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