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Question
Two cubes each of volume 125 cm3 are joined end to end to form a solid. Find the surface area of the resulting cuboid.
Solution
Let the edge of the cube be a.
As,
Volume of the cube = 125 cm3
⇒ a3 = 125
`=> a = root(3)(125)`
`=> a = 5 "cm"`
So,
Length of the resulting cuboid, `l = 2xx5 = 10 "cm",`
Breath of the resulting cuboid, b = 5 cm and
Height of the resulting cuboid, h = 5 cm
Now,
Surface area of the resulting cuboid = 2 (lb + bh + hl)
`= 2 xx (10xx5+5xx5+5xx10)`
`= 2xx(50+25+50)`
`=2xx125`
`=250 cm2`
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