Three copper cubes whose edges measure 5 cm, -Maths 9th

Three copper cubes whose edges measure 5 cm, -Maths 9th
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Let a cm be the edge of new cube. Then volume of the new cube = Sum of the volumes of three cubes. ⇒ a3 = 53 + 43 + 33 = 125 + 64 + 27 ⇒ a3 = 216    ⇒ a3 = 63    ⇒ a = 6 cm  ∴   Surface area of the new cube = 6a2 = 6 x 62 = 216 cm2
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If three cubes of copper, each with an edge 6 cm, 8 cm and 10 cm respectively are melted to form a single cube, -Maths 9th

Description : If three cubes of copper, each with an edge 6 cm, 8 cm and 10 cm respectively are melted to form a single cube, -Maths 9th

Last Answer : 20.8 cm Let the edge of the single cube be ‘a’ cm. Then, total volume melted = Volume of cube formed ⇒ (6)3 + (8)3 + (10)3 = a3 ⇒ a3 = 216 + 512 + 1000 = 1728 ... Diagonal of the new cube = 3–√a=(3–√×12)3a=(3×12) cm = 20.8 cm (approx.)

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Last Answer : When two cubes of side 2 cm each are joined end to end then, Length (l) = (2 + 2) = 4cm Breadth (b) = 2 cm; Height (h) = 2 cm ∴ Volume of cuboid = lbh = 4 x 2 x 2 = 16 cm3

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

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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

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Description : Two cubes of side 2 cm each are joined end to end. Find the volume of the cuboid so formed. -Maths 9th

Last Answer : When two cubes of side 2 cm each are joined end to end then, Length (l) = (2 + 2) = 4cm Breadth (b) = 2 cm; Height (h) = 2 cm ∴ Volume of cuboid = lbh = 4 x 2 x 2 = 16 cm3

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

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Description : Construct an equilateral triangle whose altitude is 7 cm -Maths 9th

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Last Answer : This answer was deleted by our moderators...

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Description : Three cubes of side 3 cm. 4 cm, 5 cm respectively are melted to form a new cube. The side of the new cube will be a) 6cm b) 6.5 cm c) 70cm d) 5 cm e) 4.5 cm

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