Question

A room 9 m long, 6 m broad and 3.6 m high has one door 1.4 m by 2 m and two windows, each 1.6 m by 75 cm, find :

1. The area of 4 walls, excluding doors and windows
2. The cost of white washing the walls from inside at the rate of 22.50 per m squre
3. The cost of painting its ceiling at 25 per m squre

Answer 1

2(lb+bh) is the area of 4 sides of the room
2(lb+bh)-[(1.4×2)+(2×1.6×0.75)]
2(9×6+6×3.6) - [2.8+2.4]
2(54+21.6) - (5.2)
2(75.6)-5.2
151.2-5.2
146

please mark it as the brainliest

Answer 2

area of 4 walls=2(lb+bh)

                        =2(9 x 3.6+6 x 3.6)m^2

                        =2(32.4+21.6)m^2

                        =108 m^2

NOW,

area of door= 1.4 x 2 = 2.8 m^2

area of two windows= 2(0.75 x 1.6)m^2

                                   =2.4 m^2

1.area of 4 walls excluding doors and windows= (108-2.4-2.8)m^2

                                                                              =102.8 m^2

2.cost of painting walls=₹(102.8 x 22.5)

                                      =₹2313

3.area of ceiling=l x b=(9 x 6)m^2= 54 m^2

cost of painting 54 m^2=₹(54 x 25)=₹1350

hope it would help u guys!!!

please mark me as brainliest guys