A CMOS inverter, designed to have a mid-point voltage V_I equal to half of V_dd, as shown in the figure, has the following parameters :

V_dd = 3 V

μ_nC_ox = 100 μA/V² ; V_tn = 0.7 V for nMOS

μ_nC_ox = 40 μA/V² ; |V_tp| = 0.9 V for pMOS

The ratio of  to  is equal to __________ (rounded off to 3 decimal places).