Incorrect. The pool will have $\displaystyle{2.5}{x}\usepackage{cmbright}\Huge\$ gallons in $\displaystyle{x}\usepackage{cmbright}\Huge\$ minutes. In 1 minute it will have $\displaystyle{2.5}\cdot{1}={2.5}\usepackage{cmbright}\Huge\$ gallons, in 2 minutes it will have $\displaystyle{2.5}\cdot{2}={5}\usepackage{cmbright}\Huge\$ gallons, and in 3 minutes it will have $\displaystyle{2.5}\cdot{3}={7.5}\usepackage{cmbright}\Huge\$ gallons. Can you use this logic to figure out how long it will take the pool to reach half of 50 gallons?