Q7 of 76 Page 18

A 4 cm cube is cut into 1 cm cubes. Calculate the total surface area of all the small cubes.

Given,


Original edge of cube = 4 cm


Original volume of cube = 43 = 64 cm3


After cutting ,


Edge of cube = 1 cm


Hence volume of new cube = 13 = 1 cm3


Number of small cubes thus formed =


Hence , total surface area of 64 cubes = 64× 6a2 = 64×6 = 384 m2


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