Question

The internal measures of a cuboidal room are 16 m × 8 m × 6 m. Find the total cost of

whitewashing all four walls of a room, if the cost of white washing is ₹ 4 per m2

. What will be

the cost of white washing if the ceiling of the room is also whitewashed​

Answer 1

$\huge\underline\mathcal\red{★Answer:}$

★Given:

Length of room = 16 m

Breadth of room = 8 m

Height of room = 6m

$\implies$To find cost of whitewashing , first we have to find area to be whitewashed.

★Finding Area to be whitewashed:

$\implies$Given:

4 walls and ceiling are whitewashed.

So,

Area Painted = Area of 4 walls

★Area of 4 walls :

=2h(l+b)

=2×6(16+8)

=12×24

= 228${m}^{2}$

★Area of ceiling :

= 16×8

= 128${m}^{2}$

$\implies$ Thus ,

Area of 4 walls +Area of ceiling

=228 ${m}^{2}$ + 128${m}^{2}$

= 356 ${m}^{2}$

★Cost of painting 4 walls :

$\implies$Cost of whitewashing 1${m}^{2}$= Rs.4

$\implies$Cost of whitewashing 228${m}^{2}$

$\implies$Rs.4×228

$\implies$Rs.912

$\therefore$So, Rs 912is required to paint 4 walls.

★Cost of painting 4 walls+ ceiling:

$\implies$Cost of whitewashing 1${m}^{2}$= Rs.4

$\implies$Cost of whitewashing 464${m}^{2}$

$\implies$Rs.464×4

$\implies$Rs.1856

$\therefore$So, Rs.1856 is required to paint 4 walls+ ceiling..