Two cubes each of edge 12 cm are joined end to end. What is the surface area of the new cuboid formed?

Updated on May 31, 2025 | By Learnzy Admin

Given:
Edge of each cube = 12 cm
When two cubes are joined end to end, the new shape is a cuboid.

Step 1: Find the dimensions of the cuboid

Length = 12 cm + 12 cm = 24 cm
Breadth = 12 cm
Height = 12 cm

Step 2: Use the surface area formula for a cuboid

Surface Area = 2 × (length × breadth + breadth × height + height × length)
Surface Area = 2 × (24 × 12 + 12 × 12 + 12 × 24)
Surface Area = 2 × (288 + 144 + 288)
Surface Area = 2 × 720 = 1440 cm²

Hence surface area of the new cuboid  is 1440 cm²

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