NCERT · Class 9 · Mathematics · Surface Areas and VolumesThe total surface area of a cuboid of dimensions $l$, $b$, and $h$ is given by:
Step-by-Step Solution
A cuboid has 6 rectangular faces in 3 pairs of identical dimensions: $(l \times b)$, $(b \times h)$, and $(h \times l)$. The total surface area is the sum of the areas of all 6 faces, which is $2(lb + bh + hl)$. Therefore, the correct option is $2(lb + bh + hl)$.
Detailed Options Breakdown
Option : lbh
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Surface Areas and Volumes.
Option 1: 2(lb + bh + hl) (Correct Answer)
Correct choice. Refer to the step-by-step verified solution guidelines above for details.
Option 2: 2(l + b + h)
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Surface Areas and Volumes.
Option 3: 6lbh
Incorrect choice. This distractor represents a common misunderstanding of the core principles of Surface Areas and Volumes.
💡 Study Guide: This question tests core syllabus concepts from Surface Areas and Volumes. For formulas, key summaries, and mock exam reference guides, read the full Surface Areas and Volumes Revision Notes.