Question

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: i) the area of the sheet required for making the box. ii) the cost of sheet for it, if a sheet measuring 1 sqm costs rs. 20.

Answer 1

Question: . 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:

. 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:(i) The area of the sheet required for making the box.

. 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:(i) 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.

$\huge\star{\green{\underline{\mathfrak{Answer: -}}}}$

Length of plastic box (l) = 1.5 m

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 m

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 mDepth of plastic box (h) = 0.65 m

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 mDepth of plastic box (h) = 0.65 m(i) The area of sheet required to make the box is equal to the surface area of the box excluding the top.

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 mDepth of plastic box (h) = 0.65 m(i) The area of sheet required to make the box is equal to the surface area of the box excluding the top.Surface area of the box = Lateral surface area + Area of the base

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 mDepth of plastic box (h) = 0.65 m(i) The area of sheet required to make the box is equal to the surface area of the box excluding the top.Surface area of the box = Lateral surface area + Area of the base= 2(l+b)×h + (l×b)

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 mDepth of plastic box (h) = 0.65 m(i) The area of sheet required to make the box is equal to the surface area of the box excluding the top.Surface area of the box = Lateral surface area + Area of the base= 2(l+b)×h + (l×b)= 2[(1.5 + 1.25)×0.65] + (1.5 × 1.25) m2

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 mDepth of plastic box (h) = 0.65 m(i) The area of sheet required to make the box is equal to the surface area of the box excluding the top.Surface area of the box = Lateral surface area + Area of the base= 2(l+b)×h + (l×b)= 2[(1.5 + 1.25)×0.65] + (1.5 × 1.25) m2 = (3.575 + 1.875) m2

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 mDepth of plastic box (h) = 0.65 m(i) The area of sheet required to make the box is equal to the surface area of the box excluding the top.Surface area of the box = Lateral surface area + Area of the base= 2(l+b)×h + (l×b)= 2[(1.5 + 1.25)×0.65] + (1.5 × 1.25) m2 = (3.575 + 1.875) m2 = 5.45 m2

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 mDepth of plastic box (h) = 0.65 m(i) The area of sheet required to make the box is equal to the surface area of the box excluding the top.Surface area of the box = Lateral surface area + Area of the base= 2(l+b)×h + (l×b)= 2[(1.5 + 1.25)×0.65] + (1.5 × 1.25) m2 = (3.575 + 1.875) m2 = 5.45 m2 The sheet required required to make the box is 5.45 m2

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 mDepth of plastic box (h) = 0.65 m(i) The area of sheet required to make the box is equal to the surface area of the box excluding the top.Surface area of the box = Lateral surface area + Area of the base= 2(l+b)×h + (l×b)= 2[(1.5 + 1.25)×0.65] + (1.5 × 1.25) m2 = (3.575 + 1.875) m2 = 5.45 m2 The sheet required required to make the box is 5.45 m2(ii) Cost of 1 m2 of sheet= Rs 20

Length of plastic box (l) = 1.5 mWidth of plastic box (b) = 1.25 mDepth of plastic box (h) = 0.65 m(i) The area of sheet required to make the box is equal to the surface area of the box excluding the top.Surface area of the box = Lateral surface area + Area of the base= 2(l+b)×h + (l×b)= 2[(1.5 + 1.25)×0.65] + (1.5 × 1.25) m2 = (3.575 + 1.875) m2 = 5.45 m2 The sheet required required to make the box is 5.45 m2(ii) Cost of 1 m2 of sheet= Rs 20∴ Cost of 5.45 m2 of sheet = Rs (20 × 5.45) = Rs 109 .

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 m^2 area = Rs.20.

Cost of sheet of 5.45 m^2 area =Rs (5.45×20)

= Rs.109.