Află fractiile necunoscute:
Pls repede am nevoie urgent pls

[tex]a \: + \frac{2}{7} = \frac{7}{7} \\ a \: = \frac{7}{7} - \frac{2}{7} \\ a \: = \frac{5}{7} [/tex]
[tex]b \: + \frac{5}{8} = \frac{8}{8} \\ b \: = \frac{8}{8} - \frac{5}{8} \\ b \: = \frac{3}{8} [/tex]
[tex]c \: + \frac{4}{12} = \frac{17}{12} \\ c \: = \frac{17}{12} - \frac{4}{12} \\ c \: = \frac{13}{12} [/tex]