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Question
3 cubes each of 8 cm edge are joined end to end. Find the total surface area of the cuboid.
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Solution
The dimensions of the cuboid so formed are:

Length, l = 24 cm
Breadth, b = 8 cm
Height, h = 8 cm
Since, surface area of cuboid = 2(lb + bh + lh)
= 2(24 × 8 + 8 × 8 + 24 × 8)
= 2(192 + 64 + 192)
= 2 × 448
= 896 sq cm.
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