Question

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: (i) The area of the sheet required for making the box. (ii) The cost of sheet for it, if a sheet measuring 1 m 2 costs Rs 20.

Answer 1

Dear Student,

◆ Answer -

(i) Area of required sheet = 5.45 m^2

(ii) Cost of required sheet = 109 Rs

● Explaination -

# Given -

l = 1.5 m

b = 1.25 m

h = 65 cm = 0.65 m

# Solution -

Surface area of the open box is calculated by -

Area = lb + 2lh + 2bh

Area = 1.5×1.25 + 2×1.5×0.65 + 2×1.25×0.65

Area = 5.45 m^2

Cost of the sheet will be calculated as -

Total cost = area × cost per m^2

Total cost = 5.45 × 20

Total cost = 109 Rs

Thanks dear...

Answer 2

$\huge \underline \mathbb {SOLUTION:-}$

Given:

• Length (l) of box = 1.5m

• Breadth (b) of box = 1.25 m

• Depth (h) of box = 0.65m

(i) Box is to be open at top

Area of sheet required.

= 2lh + 2bh + lb

= [2×1.5×0.65+2×1.25×0.65+1.5×1.25]m²

= (1.95 + 1.625 + 1.875)m² = 5.45 m²

(ii) Cost of sheet per m² area = Rs.20.

Cost of sheet of 5.45 m² area = Rs (5.45×20)

= Rs.109.