Since this is a direct and proportional relationship, we know that the ratio for 2.539 gal of water to 9 hours is the same as the ratio from the water in the pool after 1 hour to 1 hour. Therefore, we can simplify 2.539:9 into 0.2821111... I’m not sure what value you must round to, so I’ll assume it is to the nearest thousandth. Hence, our answer is 0.2821 gal.