Question

Based on the statements given below, choose the correct option.
S1 : Total surface area of a cuboid is the sum of areas of four of its faces, leaving the top and bottom faces.
S2 : Lateral surface area of a cuboid is the sum of areas of four of its faces, leaving the top and bottom faces.
S3 : Area of a face of a cuboid is of the form $xy,$ where $x$ and $y$ are the length and breadth of that face respectively.

• A. S1 , S3 are true
• B. S2 , S3 are false
• C. S1 and S3 are false
• D. S2 and S3 are true

Answer 1

The correct option is D

S2 and S3 are true

The outer surface of a cuboid is made up of six rectangular regions, called the faces of the cuboid.

Total surface area(or the surface area) of a cuboid is defined as the sum of the areas of all these six faces.

Lateral surface area is defined as the sum of areas of 4 faces excluding the areas of the top and bottom faces.

Area of each face of a cuboid is of the form ${}^{\prime }x{y}^{\prime }$ where $x$ and $y$ are the length and breadth of that face of the cuboid, respectively.
For example, consider the right-side face of a cuboid of dimensions $l\times b\times h$.
Length and breadth of this face are h and b respectively.
Since each face of a cuboid is a rectangular region, area of this face is given by ${}^{\prime }h\times b^{\prime }$ or ${}^{\prime }h{b}^{\prime }$.

Hence the answer.