UKMT Grey Kangaroo, 2025

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

When the length of a cuboid is reduced by $3\text{cm}$ , its surface area is reduced by $60\text{cm}^2$ . The resulting shape is a cube. What is the volume of the original cuboid, in $\text{cm}^3$ ?

(A) $75$ (B) $125$ (C) $150$ (D) $200$ (E) $225$

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