22.
[tex] \frac{1}{9} + \frac{2}{9} = \frac{3}{9} probleme \: a \: 2 \: zi[/tex]
[tex] \frac{1}{9} + \frac{3}{9} = \frac{4}{9} probleme \: a \: 3zi[/tex]
[tex] \frac{1}{9} + \frac{3}{9} + \frac{4}{9} = \frac{8}{9} in \: cele \: trei \: zile \: in \: total[/tex]
[tex] \frac{9}{9 } - \frac{8}{9} = \frac{1}{9} a \: mai \: ramas \: de \: rezolvat \: i n \: a \: 4 \: zi[/tex]
