Question

1. A plastic box 1.5 m long, 1.25 m wide and 65 cm deep is to be made. It is opened at the
top. Ignoring the thickness of the plastic sheet, determine:
(1) The area of the sheet required for making the box.
(ii) The cost of sheet for it, if a sheet measuring 1m² costs Rs 20.​

Answer 1

Step-by-step explanation:

Given:

Length of box =1.5 m, Breadth =1.25 m, Height =0.65 m

⇒Area to be white-washed = Area of cuboid − Area of base.

(i) Area of sheet requred =2lb+2bh+2lh−lb

(i) Area of sheet requred =2lh+2bh+lb .[Box is open]

=[2×1.5×0.65+2×1.25×0.65+1.5×1.25] m^2

=(1.95+1.625+1.875)m^2

=5.45 m^2

ii) Cost of sheet per m^2

area = Rs. 20

Cost of sheet of 5.45m^2

area = Rs. 5.45×20

= Rs. 109.