I'm having trouble computing cost of good available for sale and the number of units available for sale.

Question

Jan.1 Beginning inventory 600 Units @ 44Units

Feb 10 Purchases 200 Units @ 40Units

March 13 Purchases 100 Units @20Units

March 15 Sale 400Units @ 75Units

Aug. 21 Purchases 160Units @ 60Units

Sept. 5 Purchases 280Units @ 48Units

Sept. 10 Sales 200Units @ 48Units

Total Units Acquired at cost 1,340 Units and Units sold at Retail 600 Units

Answer 1

Jan 1      600  @ 44  = 26,400

Feb 10    200  @ 40  = 8,000

Mar 13    100  @ 20  = 2,000

Aug 21    160  @ 60  = 9,600

Sep 5      280  @ 48  = 13,440

Total inventory units = 600 + 200 + 100 + 160 + 280 = 1,340

Cost of the total inventory acquired = 26,400+8,000+2,000+9,600+13,440 = $59,440

Total units sold = 400 + 200 = 600

No. of units available for sale = 1,340 - 600 = 740

Cost of Goods sold using First-in-first-out (FIFO) = 400*44 + 200*44 = $26,400

Cost of Good available for sale using FIFO = $59,440 - $26,400 = $33,040

Cost of Goods sold using Last-in-first-out (LIFO) = (100*20 + 200*40 + 100*44) + ( 200*48) = $24,000

Cost of Good available for sale using LIFO = $59,440 - $24,000 = $35,440