Question

A cuboidal box of dimensions 1 m × 2 m × 1.5 m is to be painted except its bottom. Calculate how much area of the box has to be painted.
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Answer 1

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$\huge\tt{GIVEN:}$

• Length of the box, L = 2 m,
• Breadth of box, B = 1 m
• Height of box, H = 1.5 m

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$\huge\tt{TO~FIND:}$

• How much area of the box has to be painted.

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$\huge\tt{SOLUTION:}$

We know that the surface area of a cuboid = 2(lb + lh + bh)

But note that, Here the bottom part is not to be painted.

So,

Surface area of box = lb + 2(bh + hl)

↪Surface area of box = 2 × 1 + 2 (1 × 1.5 + 1.5 × 2)

↪Surface area of box = 2 + 2 (1.5 + 3.0)

↪Surface area of box = 2 + 9.0

↪Surface area of box = 11 m²

Hence,

The required surface area of the cuboidal box = 11m²

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Answer 2

GIVEN:

• Length of the box, L = 2 m,
• Breadth of box, B = 1 m
• Height of box, H = 1.5 m

TO FIND:

• How much area of the box has to be painted.

SOLUTION:

We know that the surface area of a cuboid = 2(lb + lh + bh)

But note that, Here the bottom part is not to be painted.

So,

Surface area of box = lb + 2(bh + hl)

↪Surface area of box = 2 × 1 + 2 (1 × 1.5 + 1.5 × 2)

↪Surface area of box = 2 + 2 (1.5 + 3.0)

↪Surface area of box = 2 + 9.0

↪Surface area of box = 11 m²