A meter bridge with two resistances $\mathrm{R}_1$ and $\mathrm{R}_2$ as shown in figure was balanced (null point) at 40 cm from the point P . The null point changed to 50 cm from the point P , when $16 \Omega$ resistance is connected in parallel to $R_2$. The values of resistances $R_1$ and $\mathrm{R}_2$ are $\_\_\_\_$ .