Case Manufacturing expects to have $40,000$ pounds of raw materials inventory on hand on June $30,$ the end of the current year. The company has budgeted the following production for the first four months of the coming year:

July August September October

Production $($units$)100,000120,000150,000110,000$

Case Manufacturing desires each month's ending raw materials inventory to be $20\%$ of the following month's production needs. A finished unit requires two pounds of raw materials.

Case Manufacturing's budgeted purchases of materials for September is: