A capacitor of capacitance $20 \mu \mathrm{F}$ is charged by a battery of potential $24.3 \mathrm{~V}$. The capacitor is then disconnected from the battery and is connected to another uncharged capacitor of capacitance $10 \mu \mathrm{F}$. After some time, the second capacitor is disconnected, discharged fully and is again connected to the first capacitor. If the process is repeated several times, the charge on the first capacitor at the end of the fifth process is ____ $\mu \mathrm{C}$.