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Question
The length of the longest pole that can be kept in a room (12 m × 9 m ×8 m) is
Options
144 cm2
216 cm2
180 cm2
108 cm2
Solution
216 cm2
Let the edge of the cube be a cm.
Then, length of the diagonal `=sqrt(3"a")`
or,
`sqrt(3"a") = 6sqrt(3)`
⇒ a = 6 cm
Therefore, the total surface area of the cube = 6a2
`= (6xx6xx6) "cm"^3`
= 216 cm3
Therefore, the total surface area of the cube = 6a2
= (6 × 6 × 6 ) cm3
= 216 cm3
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