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Question
Three identical cubes of side 4 cm are joined end to end. Find the total surface area and lateral surface area of the new resulting cuboid
Solution
Joint the three identical cubes we get a new cuboid
Length of the cuboid (l) = (4 + 4 + 4) cm
l = 12 cm
Breadth of the cuboid (b) = 4 cm
Height of the cuboid (h) = 4 cm
Total surface area of the new cuboid = 2(lb + bh + lh) sq.units
= 2(12 × 4 + 4 × 4 + 4 × 12)
= 2(48 + 16 + 48) cm
= 2(112) cm2
= 224 cm2
Lateral surface area of the new cuboid = 2(l + b)h sq.units
= 2(12 + 4)4 cm2
= 2 × 16 × 4 cm2
= 128 cm2
∴ T.S.A of the new cuboid = 224 cm2
L.S.A of the new cuboid = 128 cm2
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