120 ml per hour, how many hours for 1000 ml
$$\frac{1hour}{120ml}*\frac{1000ml}{1}=\frac{1000}{120}\;hours$$
$${\frac{{\mathtt{1\,000}}}{{\mathtt{120}}}} = {\frac{{\mathtt{25}}}{{\mathtt{3}}}} = {\mathtt{8.333\: \!333\: \!333\: \!333\: \!333\: \!3}}$$
8 hours and 20 minutes