Maddie noticed that many students on campus had sweatshirts with Greek organization letters or club names on them. Recognizing that there was a huge market for this attire, Maddie rented a store front and a silk screening machine to get into the sweatshirt business. Maddie's rent is $1,000 a month, including utilities. The silk screen machine leases for $300 a month. Maddie can buy sweatshirts for $10 each and determined the cost of materials for the silk screening at $2 per unit. Considering just the figures provided above, how many sweatshirts does she need to sell each month to breakeven if she prices the screened sweatshirts at $25?