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Stacked Cubes

Age 14 to 16
ShortChallenge Level Yellow star
Secondary curriculum
  • Problem
  • Solutions


Three cubes have been glued together as shown in the diagram.

The side length of the smallest cube is 3 cm.

The side length of the medium cube is 5 cm.

The side length of the largest cube is 8 cm.

What is the total surface area of the figure?





This problem is taken from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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