Odpowiedź:
[tex]e)\ \ \frac{5}{7}+\frac{2}{3}=\frac{15}{21}+\frac{14}{21}=\frac{29}{21}=1\frac{8}{21}\\\\f)\ \ 2\frac{3}{4}+1\frac{7}{10}=2\frac{15}{20}+1\frac{14}{20}=3\frac{29}{20}=4\frac{9}{20}\\\\g)\ \ \frac{5}{6}-\frac{1}{5}=\frac{25}{30}-\frac{6}{30}=\frac{19}{30}\\\\h)\ \ 2\frac{1}{5}-1\frac{3}{20}=2\frac{4}{20}-1\frac{3}{20}=1\frac{1}{20}[/tex]
5/7 + 2/3 = 15/21 + 14/21 = 29/21 = 1 i 8/21
2 i 3/4 + 1 i 7/10 = 2 i 15/20 + 1 i 14/20 = 3 i 29/20 = 4 i 9/20
5/6 - 1/5 = 25/30 - 6/30 = 19/30
2 i 1/5 - 1 i 3/20 = 2 i 4/20 - 1 i 3/20 = 1 i 1/20
