Answer:
Annie should increase the order size to 148 bottles per order and she will be able to save $91.85 per year.
Explanation:
we must calculate the economic order quantity (EOQ) in order to determine the size of the order that reduces costs:
EOQ = √[(2 x S x D) / H]
EOQ = √[(2 x 35 x 2,500) / 8] = √(175,000 / 8) = √21,875 = 147.90 ≈ 148 bottles of shampoo
total cost when ordering 100 bottles = (25 orders x $35) + (100/2 x $8) = $875 + $400 = $1,275
total cost when ordering 148 bottles = (16.89 orders x $35) + (148/2 x $8) = $591.15 + $592 = $1,183.15
Annie will save $1,275 - $1,183.15 = $91.85 per year