[m] 1\frac{1}{3}+2\frac{2}{9}= 3 + \frac{3}{9}+\frac{2}{9}=3\frac{5}{9}[/m]
[m] (1\frac{1}{3}+2\frac{2}{9})\cdot \frac{3}{16}=3\frac{5}{9}\cdot \frac{3}{16}=\frac{32}{9}\cdot \frac{3}{16}=\frac{2}{3}[/m]
то решение:
[m] (1\frac{1}{3}+2\frac{2}{9})\cdot \frac{3}{16}-1\frac{2}{3}\cdot 3=\frac{2}{3}- \frac{5}{3}\cdot 3=\frac{2}{3}-5=-4\frac{1}{3}[/m]
x=-4
y=1
z=3