4) -2 4/15 : (-1,7)

Convert mixed number to improper fraction: $$-2 \frac{4}{15} = -\frac{34}{15}$$. Convert decimal to fraction: $$-1.7 = -\frac{17}{10}$$. Divide: $$-\frac{34}{15} : (-\frac{17}{10}) = \frac{34}{15} \times \frac{10}{17} = \frac{2 \times 17}{3 \times 5} \times \frac{2 \times 5}{17} = \frac{2 \times 2}{3} = \frac{4}{3}$$.
Answer: 4/3