Question { TCS, 51998 }

A hollow cube of size 5cm is taken , with the thickness
of 1cm . it is made of smaller cubes of size 1cm . if the
outer surface of the cube is painted how many faces of the
smaller cubes remain unpainted?

Answer

438...
total number of faces=588...
surface area painted=6*5*5 cm2=150 cm2
which is equal to 150 faces of 1*1 cm2
painted faces=588-150 = 438....


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