1. Here, Length of wall (l) = 15 m, Breadth of wall (b) = 10 m and Height of wall (h) = 7 m ∴ Total Surface area of classroom = lb + 2(bh+hl) = 15 x 10 + 2 (10 x 7 + 7 x 15) = 150 + 2 (70 + 105) = 150 + 350 = 500 m² Now Required number of cans = Area of hall/Area of one can =500/100=5cms Hence, 5 cansRead more

    Here,
    Length of wall (l) = 15 m, Breadth of wall (b) = 10 m and Height of wall (h) = 7 m
    ∴ Total Surface area of classroom = lb + 2(bh+hl)
    = 15 x 10 + 2 (10 x 7 + 7 x 15)
    = 150 + 2 (70 + 105) = 150 + 350 = 500 m²
    Now Required number of cans = Area of hall/Area of one can =500/100=5cms
    Hence, 5 cans are required to paint the room.

    Class 8 Maths Chapter 11 Exercise 11.3 Solution in Video

    for more answers vist to:
    https://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-11/

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  2. (a) Given: Length of cuboidal box (l) = 60 cm Breadth of cuboidal box (b) = 40 cm Height of cuboidal box (h) = 50 cm ∴ Total surface area of cuboidal box = 2(lb+bh+hl) = 2 (60 x 40 + 40 x 50 + 50 x 60) = 2 (2400 + 2000 + 3000) = 2 x 7400 = 14800 cm² (b) Given: Length of cuboidal box (l)= 50 cm BreadRead more

    (a) Given: Length of cuboidal box (l) = 60 cm
    Breadth of cuboidal box (b) = 40 cm
    Height of cuboidal box (h) = 50 cm
    ∴ Total surface area of cuboidal box = 2(lb+bh+hl)
    = 2 (60 x 40 + 40 x 50 + 50 x 60)
    = 2 (2400 + 2000 + 3000)
    = 2 x 7400 = 14800 cm²

    (b) Given: Length of cuboidal box (l)= 50 cm
    Breadth of cuboidal box (b) = 50 cm
    Height of cuboidal box (h) = 50 cm
    ∴ Total surface area of cuboidal box = 2(lb+bh+hl)
    = 2 (50 x 50 + 50 x 50 + 50 x 50)
    = 2 (2500 + 2500 + 2500)
    = 2 x 7500 = 15000 cm²

    Hence, the cuboidal box (a) requires the lesser amount of material to make, since
    surface area of box (a) is less than that of box (b).

    Class 8 Maths Chapter 11 Exercise 11.3 Solution in Video

    for more answers vist to:
    https://www.tiwariacademy.com/ncert-solutions/class-8/maths/chapter-11/

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