Question

18) A cuboidal petrol tin has dimensions of 20 cm
16 cm x 14 cm. What is the total surface area of
a sheet of tin required to make 12 such tins?​

Answer 1

Answer:

⠀⠀⠀⌬ Dimensions = 20 cm × 16 cm × 14 cm

⠀⠀⠀⌬ TSA of tin sheet to make 12 petrol tin

• Total Surface Area of 1 Cuboidal tin :

⇒ TSA = 2(lb + bh + hl)

⇒ TSA = 2(20 × 16 + 16 × 14 + 14 × 20)

⇒ TSA = 2(320 + 224 + 280)

⇒ TSA = 2 × 824

⇒ TSA = 1648 cm²

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• TSA of 12 such cuboidal tins :

⇢ TSA = TSA of 1 tin × Number

⇢ TSA = 1648 cm² × 12

⇢ TSA = 19776 cm²

• If we want to change it into meter²

⇢ TSA = 19776 ÷ 100 m ÷ 100 m

⇢ TSA = 1.98 m²

∴ Hence, required tin will be 1.98 m².

Answer 2

Answer:

Required Answer:-

petrol tank is in the form of a cuboid

Given: Dimensions of the cuboid=20cm×16cm×14cm

Total surface area of the tin = 2(lb + bh + lh) where l = 20cm, b = 16cm and h = 14cm

∴ Total surface area of the tin = 2 (20 × 16 + 16 × 14 + 20 × 14) = 2(320 + 224‬ + 280) = 1,648‬ sq.cm

Total area of sheet required to make such 12 tins = 1648 × 12 = 19,776‬ sq.cm