Answer:
economic order quantity (EOQ) = √(2SD/H)
D = annual demand = I will assume that the company works during 250 days per year (from Monday to Friday) = 250 x 500 = 125,000
S = order cost = $2,250
H = holding cost = $275
EOQ = √[(2 x 2,250 x 125,000) / 275] = 1,430.19 ≈ 1,430 tons
cycle length:
125,000 / 1,430 = 87.4 purchases per year
365 days / 87.4 = place a purchase order every 4.2 days
total annual cost:
total costs = (87.4 x $2,250) + (125,000 x $1,100) + (1,430/2 x $275) = $196,650 + $137,500,000 + $196,625 = $137,893,275