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Question
Three cubes of each side 4 cm are joined end to end. Find the surface area of the resulting cuboid.
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Solution
Side of each cube (a) = 4 cm
We need to find the surface area of the resulting cuboid
Dimensions of the resulting cuboid,
Length (l) = 3a
Breadth (b) = a
Height (h) = a
Surface area of the cuboid,
`=2(lb + bh + hl)`
`=2[(3a) a +(a)(a) +a(3a)]`
`=2(7a^2)`
`=14a^2`
`= 14 xx 4^2`
`=224 cm^2`
Surface area of the cuboid is `224 cm^2`.
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