How to create a schedule of expected cash dispersements for purchases of raw materials (budget schedule)

Direct Materials Budget
Required production in cases	13,000	16,250	24,000	53,250
Unit of raw materials needed per case	15	15	15	15
Units of raw materials needed to meet production	195,000	243,750	360,000	798,750
Add: desired units in ending inventory	25,000	36,000	79,875	140,875
Total units of raw materials	220,000	279,750	439,875	939,625
Less units of beginning raw materials	18,000	25,000	36,000	79,000
Units of raw materials to be purchased	202,000	254,750	403,875	860,625
Cost of raw materials per pound	$ 0.35	$ 0.35	$ 0.35	$ 0.35
Cost of raw materials to be purchased	$ 70,700	$ 89,163	$ 141,356	$ 301,219

80% payables in the first month, 20% in the second month