Problems from Decimal expression of rational numbers

According to our notation; $a=17,b=1.742,m=1$ and $n=2$. Then that corresponds to the quotient $${\displaystyle \frac{b-a}{990}}={\displaystyle \frac{1.742-17}{990}}={\displaystyle \frac{115}{66}}$$

According to our notation; $a=537,b=5.373,m=3$ and $n=1$. Then that corresponds to the quotient $${\displaystyle \frac{b-a}{9.000}}={\displaystyle \frac{5.373-537}{9.000}}={\displaystyle \frac{403}{750}}$$

If we do the division we obtain ${\displaystyle \frac{7}{4}}=1,75$, which is the decimal expression. There is no repeating.

If we do the division we obtain ${\displaystyle \frac{5}{11}}=0,454545\dots$

So the repeating is $45$ and the decimal expression is $0,\widehat{45}.$

If we do the division we obtain ${\displaystyle \frac{5}{18}}=0,27777\dots$

So the repeating is $7$ and the decimal expression is $0,2\hat{7}$.