If all 216 tickets sold were faculty tickets, the revenue would be 216 * 2.5, or $540
The actual revenue collected was $450. The difference between $540 and $450 is $90.
The difference between the student and faculty tickets are $2.50-$2, or .50
$90.00 / .50 = 180 student tickets sold.
That leaves 216-180, or 36 as faculty tickets.
180 student tickets at $2 = $360
36 faculty tickets at $2.50 = $90
$360 + $90 = $450
