Question

the dimension of a room are 8m*6.5m* 4 m. find the cost of preparing its wall by a 50 cm wide wallpapers at the rate of ₹25 per metre​

Answer 1

the dimensions of room is cuboidal shape

therefore to cover the room by wallpaper is its curved surface area

c. s. a. of a cuboid is l*b*h

=8*6.5*4

=208

the cost of prep 50cm wall

the rate of per meter is $25

1 meter =100 cm

25 m =25*100cm

=2500cm

therefore for 50cm=2500/500

=5cm

Answer 2

Area of 4 walls =2(l+b)h =2(8+6.5).4 =2*14.5*4 =116m^2

50cm=0.5m

rate =25rs/m^2

cost=116*25

=2900

$2(l +b ) \times h$