The document contains calculations involving multiplication and subtraction. It multiplies 500 by 2 to get 1,000, multiplies 30 by 50 to get 1,500, and subtracts 600 from 1,500 to get 900. It then multiplies 400 by 15 to get 6,000 and subtracts 300 from 6,000 to get 5,700.