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Question
Two cubes each of volume 27 cm3 are joined end to end to form a solid. Find the surface area of the resulting cuboid.
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Solution
As , volume of a cube = 27 cm3
⇒ (edge)3 = 27
⇒ edge = `root {3}(27)`
⇒ edge = 3 cm
The length of the resulting cuboid , l = 3 + 3 = 6 cm ,
its breath , b = 3 cm and its height , h = 3 cm
Now , the surface area of the resulting cuboid = 2(lb + bh + hl)
= `2 (6 xx 3 + 3 xx 3 + 3 xx 6)`
= 2 (18 + 9 + 18)
= `2 xx 45`
= 90 cm2
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