A total of 480 black and red jerseys were produced in a factory. Each black Don jersey was sold at $56. Each red jersey was sold at $75. After all the jerseys were sold, the amount of money collected from the sale of the black jerseys was $18315 less than that of the red jerseys. (a) How many black jerseys were sold? (b) How much money was collected from the sale of the red jerseys?