Weighted Average Cost Method with Perpetual Inventory The beginning inventory for Dunne Co. and data on purchases and sales for a three-month period are as follows: Number Date Transaction of Units Per Unit Total Apr. 3 Inventory 25 $1,200 $30,000 8 Purchase 75 1,240 93,000 11 Sale 401 2,000 80,000 30 Sale 30 2,000 60,000 May 8 Purchase 60 1,260 75,600 10 Sale 50 2,000 100,000 19 Sale 201 2,000 40,000 28 Purchase 80 1,260 100,800 June 5 Sale 40 2,250 90,000 16 Sale 25 2,250 56,250 21 Purchase 35 1,264 44,240 28 Sale 44 2,250 99,000