Q4 of 32 Page 255

Two cubes each of volume 64cm2 are joined end to end together. Find the surface area of the resulting cuboid.


Given that, volume of cube is 64 cm3.


Also, volume of cube = a3 (where, a is side)


⇒ a3 = 64


⇒a = 4


⇒ Length(l) of cuboid = 2 × a = 8 cm,


Breadth(b) = height(h) = a = 4 cm


⇒ the total surface area of the resulting cuboid = 2(lb + bh + hl)


⇒ 2 × (8 × 4 + 4 × 4 + 4 × 8)


= 2 × 80


= 160 cm2


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