Yes, it is possible to sell enough additional tickets on the day of the show to meet the expensive of the show because:
330 x $5 = $1650 (amount of money earned by selling the $5's tickets)
600 - 330 = 270(tickets that are available to being sold at $7 the day of the show)
270 x 7 = $1890 (amount of money earned by selling the $7's tickets)
$1890 + $1650 =$ 3540
$3540 > $3500,so it's possible to sell enough additional tickets on the day of the show to meet the expensive of the show.
Sorry for the grammar, but I'm italian
