If the moment of inertia of a disc about an axis tangentially and parallel to its surface be I, what will be the moment of inertia about the axis tangential but perpendicular to the surface-

According to the theorem of parallel axes, the moment of inertia of the disc about an axis tangentially and parallel to the surface is given byI==MR24+MR2=54MR2 ⇒MR2=4I5 given by I′=MR22+MR2=32MR2=324I5=6I5