Question

Question 1 (ii)
A plastic box 1.5 m long, 1.25 m wide and 65 cm deep, is to be made. It is to be open at the top. Ignoring the thickness of the plastic sheet, determine:
(ii)The cost of the sheet for it, if a sheet measuring $1m^2$ costs Rs. 20.

Answer 1

It is given that, length (l) of box = 1.5 m
Breadth (b) of box = 1.25 m
Depth (h) of box = 0.65 m
Box is to be open at top.
Area of sheet required
$=2lh+2bh+lb=[2\times 1.5\times 0.65+2\times 1.25\times 0.65+1.5\times 1.25]m^2=(1.95+1.625+1.875)m^2=5.45m^2$
(ii) Cost of sheet per $m^2$ area = Rs. 20
Cost of sheet having $5.45m^{2}area=Rs(5.45\times 20)$
= Rs. 109