You probably forgot to take into account the function room charge of $280, and divided the $1,500 by $40. If $\displaystyle{p}=\usepackage{cmbright}\Huge\$ the number of people, then the company is charged $\displaystyle{40}{p}\usepackage{cmbright}\Huge\$ dollars for the dinners, plus the $280 for the room. So $\displaystyle{40}{p}+{280}={1},{500}\usepackage{cmbright}\Huge\$ . The correct answer is 30 people.