3.
b)
[tex] \frac{2}{3} + \frac{1}{6} = \frac{4}{6} + \frac{1}{6} = \frac{5}{6} [/tex]
c)
[tex]1 \frac{5}{6} + 4 \frac{1}{12} = 1 \frac{10}{12} + 4 \frac{1}{12} = 5 \frac{11}{12} [/tex]
d)
[tex] \frac{4}{5} - \frac{3}{10} = \frac{8}{10} - \frac{3}{10} = \frac{5}{10} [/tex]
e)
[tex] \frac{8}{3} - \frac{8}{9} = \frac{24}{9} - \frac{8}{9} = \frac{16}{9} = 1 \frac{7}{9} [/tex]
f)
[tex]2 \frac{1}{2} - \frac{1}{4} = 2 \frac{2}{4} - \frac{1}{4} = 2 \frac{1}{4} [/tex]
Myślę że pomogłem ;)