Question

The length, breadth and height of a room are 5 m, 4 m and 3 m respectively. Find
the cost of white washing the inner of the room and ceiling at the rate of 50
per square metre.​

Answer 1

Answer:

total area for white washing = 4 walls + ceiling

area of 4 walls + ceiling = 2(lh + bh) + lb

                                       = 2(5*3 + 4*3) + 5*4

                                       = 2(15 + 12) + 20

                                       = 2*27 + 20

                                       = 54 + 20

                                       = 74 meter square     ans .

Step-by-step explanation:

Answer 2

$\sf \large \underline \purple{ Question - }$

The length, breadth and height of a room are 5 m, 4 m and 3 m respectively. Find

the cost of white washing the inner of the room and ceiling at the rate of 50

per square metre.

$\sf \large \underline \purple{Answer \: - }$

Length, breath and height of a room are 5m, 4m and 3m respectively,

Area of 4 walls of the room = 2h( l + b )

$\implies \: 2 \times 3(5 + 4)$

$\implies \: 6 \times 9$

$\implies \: 54 \: { \sf m}^{2}$

Area of the celling = l × b

$\implies \: 5 \times 4$

$\implies \: 20 { \sf \: m}^{2}$

Total area = area of celling + area of 4 walls

= 54 + 20

= 74 m²

the cost of white washing the inner of the room and ceiling at the rate of 50 per square metre.

$\implies \: 74 \times 50$

$\implies \sf \red{ 3700Rs}$