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Question
Two cubes, each of volume 512 cm3 are joined end to end. Find the surface area of the resulting cuboid.
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Solution
Given that
Volume of cube = `512 cm^3`
⇒`"side"^3= 512`
⇒`"side"^3=8^3`
⇒`"side"^3 = 8cm`
Dimensions of new cuboid formed
`l=8+8=16 cm,b= 8cm,h=8cm`
`"Surface area"= 2(lb+bh+hl) `
`2[16(8)+8(8)+16(8)]=2[256+64]`
`= 640cm^2`
`∴"Surface area is 640cm"^2`
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