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 walls of the room and the ceiling at the rate of 7.50 per m²​

Answer 1

Answer:

here is your answer

Step-by-step explanation:

thank you

Answer 2

Answer:

₹ 555.00

Step-by-step explanation:

Given:-

Length $(l)=5m$

Breadth $(b)=4m$

Height $(h)=3m$

Rate of white-washing per $m^{2}=7.50$

To find:-

Cost of white-washing the walls of the room and the ceiling

Solution

Lateral Surface Area of a cuboid $=2(lh+bh)$

⇒ $2[(5)(3)+(4)(3)]$

⇒ $2(15+12)$

⇒ $2(27)$

⇒ $54 m^{2}$

Area of the ceiling = $lb$

⇒ $(5)(4)$

⇒ $20m^{2}$

Surface area of the walls of the room and the ceiling = Lateral Surface Area of a cuboid + Area of the ceiling

Surface area of the walls of the room and the ceiling $=54+20$

Surface area of the walls of the room and the ceiling $=74m^{2}$

Rate of white-washing per $m^{2}=7.50$

Cost of white-washing the walls of the room and the ceiling $=(7.50)(74)$

Cost of white-washing the walls of the room and the ceiling $=555.00$

Cost of white-washing the walls of the room and the ceiling $=$ ₹ 555.00

∴ The cost of white-washing the walls of the room and the ceiling $=$ ₹ 555.00