Question

B Mary wants to keep her christmas tree in a wooden box covered
with coloured paper. She wants to know how much paper she needs
to buy. The above mentioned box is 80 cm long, 40 cm wide and
20 cm high. And if the paper is 40 cm square sheets then how many
sheets are needed.​

Answer 1

Given that mary wants to paste the paper on the outer surface of the box. The quantity of the paper required would be equal to the surface area of the box which is of the shape of cuboid. The dimension of the box are  

Length l=80 cm

Breath b=40 cm

Height h=20 cm

Surface area of the box =2[lb+bh+hl]

                                       =2[80×40+40×20+20×80]

                                       =2×5600

                                       =11200 cm  

2

 

Area of each sheet of paper =40×40

                                               =1600 cm  

2

 

∴ Number of sheets required =  

1600

11200

​  

 

                                                 =7

pls mark as brainliest