In a series LR circuit with ${\mathrm{X}}_L=R.$  Power factor is ${\mathrm{P}}_1.$  If a capacitor of capacitance  $\mathrm{C}$ with  ${\mathrm{X}}_C=X_L$ is added to the circuit the power factor becomes ${\mathrm{P}}_2.$  The ratio of ${\mathrm{P}}_1$  to ${\mathrm{P}}_2$  will be: