In both the cases 'cr' is at (+)3 state having d3 configuration.... so irrespective of the type of ligand all 3 e-s singly occupy 3 t2g orbitals & consequently the CFSE =[3×(-0.4)]=(-)1.2delta(o)

but the answer is given Cr(H20)6Cl3 delta (o) is less than Cr( NH3)6]Cl3 .