
Let mass of lamina =m, and length of side =l, then moment of inertila of lamina about an axis passing through G and perpendicular to the plane.
I0∝ml2
I0=kml2

Let moment of inertila of DEF=I1 about G
then, I1=16I0
then,IADE=IBDF=IEFC=I2
3I2+I1=I0
3I2+16I0=I0
⇒ I2=165I0
So, Moment of inertila of DECB=2I2+I12(165I0)+(16I0)
=1611I0