Final answer:
When companies use different depreciation methods for book and tax purposes, they typically use an accelerated depreciation method for tax purposes to minimize taxable income early on.
Step-by-step explanation:
It is not unusual for a company to use different depreciation methods for book and tax purposes. When this happens, the firm usually uses an accelerated depreciation method for tax purposes. This approach allows a company to minimize taxable income in the earlier years of an asset's life, resulting in delayed tax payments and potential cash flow benefits. For book purposes, firms often use the straight-line depreciation method, which spreads the cost of the asset evenly over its useful life, offering a more balanced view of expenses for financial reporting.