會計book value的問題

Net book value means there is a gross amount (Book Value) less another amount to give a Net Book Value. For example, cost of office equipment $100, this is the book value. If the provision for depreciation is $30, then the Net Book Value of Office Equipment is therefore $70.
By the same principle, in Debtors Account, the book value of debtors means the gross amount. The book value - provision for doubtful debts = Net Book Value.