Question

Find the surface area of box whose length, breadth and height are 12cm ,8cm and 5cm respectively

Answer 1

Surface area =2(lh*+lb+bh)

surface area =2*(8*12+5*8+12*5)=

2(96+40+60)=392cmsq

Answer 2

Given:

The box is cuboid because its dimensions are not equal.

length of cuboid = 12 cm

breadth of cuboid = 8 cm

height of cuboid = 5 cm

To find:

Surface area of cuboid =?

Step wise solution:

• The surface area of a cuboid can be its total surface area (TSA) or lateral surface area (LSA)
• Since, the question does not specify we will compute the TSA and LSA of cuboid, both.
• Total surface area is the sum of the area of all the surfaces of a cuboid.
• It is calculated from the following formula:

TSA of cuboid = 2 (Length x Breadth + breadth x height + Length x height)

TSA = 2 (12 cm × 8 cm + 8 cm × 5 cm + 12 cm × 5 cm)

TSA = 2 (96 cm + 40 cm + 60 cm)

TSA = 2 (196 cm)

TSA = 392 cm²

• Lateral surface area is the sum of the area of four vertical faces of cuboids.
• Lateral surface area of cuboid can be calculated as follows:

LSA = 2 height(length + breadth)

LSA = 2 × 5 cm (12 cm + 8 cm)

LSA = 10 cm (20 cm)

LSA = 200 cm²

• Hence the total surface area of a cuboid is 392 cm² while the lateral surface area of a cuboid is 200 cm².