In the following reaction, $\mathrm{P}$ gives two products $\mathrm{Q}$ and $\mathrm{R}$ each in $40\%$ yield.

If the reaction is carried out with $420 \mathrm{mg}$ of $\mathrm{P}$, the reaction yields $108.8 \mathrm{mg}$ of $\mathrm{Q}$. The amount of $\mathrm{R}$ produced in the reaction is closest to