有關 Closing cash balance如何計算? - 金融分析師

請教一下,CFA的課本中有題算Closing cash balance的
可是用公式怎麼算,都和答案不同

M&J 開始營運於20X0,01.01,且當時的BS如下:
Cash $10,000, Common stock $10,000

經過了一年,到了20X0,12,31時,BS如下
Cash $ 5,000 Common stock $10,000
Inventory 10,000 Pretax income$ 5,000


FIFO Weighted Average LIFO
Sales $25,000 $25,000 $25,000
COGS 8,000 9,000 10,000
Other Exp 12,000 12,000 12,000
Pretax income 5,000 4,000 3,000
Income Tax 2,000 1,600 1,200
Net income 3,000 2,400 1,800
Dividends paid 1,500 1,200 900
Retained earing 1,500 1,200 900
Cash fm operating(7,000) (6,600) (6,200)
Closing inventory10,000 9,000 8,000
Inventory Pur. 18,000 18,000 18,000
Closing cash balance ? ? ?

解答中的公式有註明: Cash balance=$10,000+Cash from operations
FIFO Weihjted Ave. LIFO
Closing cash balance 1,500 2,200 2,900
我怎樣也算不出答案,究竟是答案錯了,還是我公式錯了
謝謝大家


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