Cell A2: the date of incoming goods;
Cell B2: the number of packages of 500KG/BAG; assuming 1200
Cell C2: the number of packages of 1000KG/BAG; assuming 30
Cell D2: the number of packages of 25KG/BAG; assuming 462
Cell E2: the number of boards; Formula E2 = B2 + C2 + CEILING (D2/40,1)
EXCEL automatically calculated to 1242, that is, 25KG/BAG of 462 packages counted as 12 boards.