am nevoie rapit ma puteti ajuta vrog plizzz

Răspuns:
a)[tex](\frac{2}{9}+\frac{7}{9})-\frac{3}{4}=1-\frac{3}{4}=\frac{1}{4}[/tex]
b)[tex](2\frac{1}{4}*\frac{3}{11}):\frac{9}{11}=(\frac{1}{2}*\frac{3}{11})*\frac{11}{9}=\frac{3}{2*11}*\frac{11}{9}=\frac{1}{6}[/tex]