\( 9 \frac{5}{18} - 4 \frac{7}{18} = 8 \frac{23}{18} - 4 \frac{7}{18} = 4 \frac{16}{18} = 4 \frac{8}{9} \) литра.
\( 4 \frac{8}{9} - 3 \frac{1}{18} = 4 \frac{16}{18} - 3 \frac{1}{18} = 1 \frac{15}{18} = 1 \frac{5}{6} \) литра.
\( 9 \frac{5}{18} + 1 \frac{5}{6} = 9 \frac{5}{18} + 1 \frac{15}{18} = 10 \frac{20}{18} = 11 \frac{2}{18} = 11 \frac{1}{9} \) литра.
Ответ: 11 1/9 литра.