Oblicz ! a) 2/3 *(7 4/20 - 3 3/4) = b) 74/5 -1 1/5 * 2 1/2 = Błagam pomóżcie !  Daje naj naj ;)

a) [latex]frac{2}{3}*(7frac{4}{20}-3frac{3}{4})=frac{2}{3}*(frac{144}{20}-frac{15}{4})=frac{2}{3}*(frac{144}{20}-frac{75}{20})=frac{2}{3}*frac{69}{20}=\\frac{1}{3}*frac{69}{10}=frac{1}{1}*frac{23}{10}=frac{23}{10}=2frac{3}{10}[/latex] b) [latex]frac{74}{5}-1frac{1}{5}*2frac{1}{2}=frac{74}{5}-frac{ ot6_{3}}{ ot5_{1}}*frac{ ot5_{1}}{ ot2_{1}}=frac{74}{5}-frac{3*1}{1*1}=frac{74}{5}-frac{3}{1}=frac{74}{5}-frac{15}{5}=frac{59}{5}=11frac{4}{5}[/latex]