Cześć!
Zadanie 8
[tex]6\frac{2}{9}-2\frac{5}{6}=6\frac{2\cdot2}{9\cdot2}-2\frac{5\cdot3}{6\cdot3}=6\frac{4}{18}-2\frac{15}{18}=5\frac{22}{18}-2\frac{15}{18}=3\frac{7}{18}\\\\\boxed{\text{Odp}. \ \text{C}}[/tex]
Zadanie 9
[tex]1 \ godzina=60 \ minut\\\\4 \ godziny=4\cdot60 \ minut=240 \ minut\\\\\frac{5}{12} \ godziny=\frac{5}{12}\cdot60 \ minut=5\cdot5 \ minut=25 \ minut\\\\4\frac{5}{12} \ godziny=240 \ minut+25 \ minut=265 \ minut\\\\\boxed{\text{Odp}. \ \text{D}}[/tex]
Zadanie 10
[tex]4\frac{2}{5}=\frac{4\cdot5+2}{5}=\frac{20+2}{5}=\frac{22}{5}\\\\\text{liczba odwrotna do} \ \frac{22}{5} \ \text{to} \ \frac{5}{22}\\\\\boxed{\text{Odp}. \ \text{A}}[/tex]
