9) 2 1/2 : 1 1/3 =

9) $$2\frac{1}{2} : 1\frac{1}{3} = \frac{5}{2} : \frac{4}{3} = \frac{5}{2} \cdot \frac{3}{4} = \frac{5 \cdot 3}{2 \cdot 4} = \frac{15}{8} = 1\frac{7}{8}$$

Ответ: $$1\frac{7}{8}$$