Charity Event Ticket Sales Problem

A school is organizing a charity event and needs to distribute tickets. Each ticket costs $12. The school wants to raise

$960 to fund a new library. Let N represent the number of tickets sold. The school also has a special offer: for every 4 tickets sold, they will give away 1 ticket free. If they sell

5(N/4) tickets as a promotion, how many tickets does the school need to sell, including the free tickets, to meet their fundraising goal?