Rozszerz ułamek : 7/9 = Skróć ułamki : 4/8 = 12/15 = Oblicz. 3/7 + 1/3 =

7/9 = 14/18 4/8 = 1/2 12/15 = 4/5 3/7 + 1/3 = 9/21 + 7/21 = 16/21

[latex]frac{7}{9} = frac{7*2}{9*2}=frac{14}{18}\\\ frac{4}{8} =frac{1}{2}\\ frac{12}{15} =frac{4}{3}\\\frac{3}{7} + frac{1}{3} =frac{9}{21} + frac{7}{21} =frac{16}{21} [/latex]