Question

Find the cost of painting 3 iron boxes at the rate of rs5 per square metre, whose dimension are 1.5m × 0.85m × 0.20m, 2m × 0.65m × 0.35m and 2m × 0.90m × 0.45m ????answer 

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Answer 1

Question : Find the cost of painting 3 iron boxes at the rate of Rs 5 per square metre, whose dimension are 1.5m × 0.85m × 0.20m, 2m × 0.65m × 0.35m and 2m × 0.90m × 0.45m.

Solution : We know that the area of cobiod

⇒ 2 (lb+bh+hl) where,

l=length of cuboid

b=breadth of cuboid

and, h=height of cuboid

StEp-BY-SteP-ExPlaNTatIoN :

Area of box with given dimesions.

⇒1.5m 0.85m and 0.20m

⇒2 (lb+bh+hl)

⇒2(1.5×0.85 + 0.85×0.20 + 0.20×1.5)

⇒2(1.275+0.17+0.3)

⇒6.55 m²

Area of box with dimesions

2m 0.65m and 0.35m

⇒2(2×0.65 + 0.65×0.35 + 0.35×2)

⇒2(1.3+0.2275+0.7)

⇒4.455 m²

Area of box with dimesions

⇒ 2m 0.90m and 0.45m

⇒2(2×0.90+0.90×0.45+0.45×2)

⇒2(1.8+0.405+0.9)

⇒ 6.21 m²

Now, The total area of three boxes.

⇒Area of box with dimesions (1.5m,0.85m 0.20m) + Area of box with dimesions (2 m 0.65m 0.35m) + Area of box with dimesions (2m,0.90m 0.45m).

⇒ (6.55+4.455+6.21)m²

⇒17.215 m²

⇒Now, Cost of painiting per m² = Rs. 5 Cost of

painiting 17.215 m²

⇒Rs (5 ×17.215)

⇒₹ 86.075