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Geometry Difficulty 2.1 Junior Find the answer

Two identical smaller cubes are stacked next to a larger cube. Each of the two smaller cubes has a volume of 8. What is the volume of the larger cube?

A number or a short expression. Spacing and $ signs are ignored.

Solution

Since 2×2×2=82 \times 2 \times 2=8, a cube with edge length 2 has volume 8. Therefore, each of the cubes with volume 8 have a height of 2. This means that the larger cube has a height of 2+2=42+2=4, which means that its volume is 43=4×4×4=644^{3}=4 \times 4 \times 4=64.

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