Find the lateral surface area and total surface area of a cuboid of length 80 cm, breadth 40 cm and height 20 cm. -Maths 9th

1 Answer

Answer :

Length of cuboid (l) = 80 cm Breadth (b) = 40 cm Height (h) = 20 cm (i) ∴ Lateral surface area = 2h(l + b) = 2 x 20(80 + 40) cm² = 40 x 120 = 4800 cm² (ii) Total surface area = 2(lb + bh + hl) = 2(80 x 40 + 40 x 20 + 20 x 80) cm² = 2(3200 + 800 + 1600) cm² = 5600 x 2 = 11200 cm²

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Description : Two cubes of edge 6 cm are joined to form a cuboid. Find the total surface area of the cuboid. -Maths 9th

Last Answer : When two cubes are joined end to end, then Length of the cuboid = 6 + 6 = 12 cm Breadth of the cuboid = 6 cm Height of the cuboid = 6 cm Total surface area of the cuboid = 2 (lb + bh + hi) = 2(12 x6 + 6×6 + 6×12) = 2(72 + 36 + 72) = 2(180) = 360 cm2

Description : Two cubes of edge 6 cm are joined to form a cuboid. Find the total surface area of the cuboid. -Maths 9th

Last Answer : When two cubes are joined end to end, then Length of the cuboid = 6 + 6 = 12 cm Breadth of the cuboid = 6 cm Height of the cuboid = 6 cm Total surface area of the cuboid = 2 (lb + bh + hi) = 2(12 x6 + 6×6 + 6×12) = 2(72 + 36 + 72) = 2(180) = 360 cm2

Description : The length, breadth and height of a rectangular parallelopiped are in the ratios 6 : 3 : 1. If the surface area of a cube is equal -Maths 9th

Last Answer : answer:

Description : The surface area of cuboid is 1792 sq cm. -Maths 9th

Last Answer : Let the height = x cm, then breadth = 2x cm length = 4x cm According to formula, 2(lb + bh + lh) = 1792 2(8x2 + 2x2 + 4x2) = 1792 28x2 = 1792 ⇒ x 2 = 1792/28 = 64 ⇒ x = 8 Length = 8 X 4 = 32 cm

Description : Three equal cubes are placed adjacently in a row. Find the ratio of total surface area of the new cuboid to that of the sum of the surface areas of the three cubes. -Maths 9th

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Description : The external length, breadth and height of a closed box are 10cm, 9cm and 7cm respectively. The total inner surface area of the box is 262 sq.cm. If the walls of the box are of uniform thickness “t” cm, then “t” equals a) 1cm b) 23/3 cm c) 28/9 cm d) 42.5 cm

Last Answer : a) 1cm

Description : Find the lateral surface area and total surface area of a cube of edge 10 cm. -Maths 9th

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Description : The perimeter of one face of a cube is 20 cm. Find the lateral surface area of the cube. -Maths 9th

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Description : The perimeter of one face of a cube is 20 cm. Find the lateral surface area of the cube. -Maths 9th

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Description : The length, breadth and height of a room are 5 m, 4 m and 3 m respectively. Find the cost of white washing the walls of the room and the ceiling at the rate of ₹7.50 m². -Maths 9th

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Description : The length, breadth and height of a room are 5 m, 4 m and 3 m respectively. Find the cost of white washing the walls of the room and ceiling at the rate of Rs 7.50 per m2. -Maths 9th

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Description : The length, breadth and height of a room are 5 m, -Maths 9th

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Description : A spherical ball is divided into two equal halves. If the curved surface area of each half is 56.57 cm?, find the volume of the spherical ball.11531/cylinder-radius-halved-and-height-doubled-then-find-volume-with-respect-original-volume -Maths 9th

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Description : The lateral surface area of a cube is 256 m2. The volume of the cube is -Maths 9th

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Last Answer : answer:

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Description : Write the coordinates of the vertices of a rectangle whose length and breadth are 5 and 3 units respectively, -Maths 9th

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Description : The areas of three adjacent faces of a cuboid -Maths 9th

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