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 plastic sheet determine the area of the sheet required for making the box

Answer 1

L = 1.5m = 150cm ,

B = 1.25m = 125cm,

H = 65cm.

area of total all sides = 2(LB + BH + HL)

open at top means

area of box required = 2(LB + BH + HL) - (LB)

area of box required = 2LB + 2BH + 2HL - LB

area of box required = LB +2(BH + HL)

area of box required = (150*125) + 2(125*65 + 65*150)

area of box required = (18750) + 2(8125 + 9750)

area of box required = (18750) + 2(17875)

area of box required = (18750) + (35750)

area of box required = ( 18750 + 35750 )

area of box required = 54500cm²

area of box required = 5.45m²

Answer 2

Question ::-

A plastic box 1.5 m long 1.25 m wide and 0.65 M deep is to be made it is to be open at the top growing the thickness of the plastic sheet determine the area of the sheet required for making the box ?

Given ::-

• Length = 1.5m

• Breadth = 1.25m

• Depth = 0.65m

• Box is to be open at top

To find ::-

• Area of sheet required ?

• Cost of sheet per ${m}^{2}$?

Solution ::-

(i) Area of sheet required .

2lh + 2bh + lb

[2×1.5×0.65+2×1.25×0.65+1.5×1.25]

[1.95+1.625+1.875] ${m}^{2}$

5.45 ${m}^{2}$

____________

(ii) Cost of sheet per ${m}^{2}$ = Rs. 20

Cost of sheet per 5.45${m}^{2}$ = 5.45×20

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀= Rs 109