Final answer:
To calculate the depreciation expense using the diminishing-balance method, divide the difference between the cost and residual value by the useful life to find the straight-line rate. Multiply the beginning book value by the depreciation rate to find the expense for each year.
Step-by-step explanation:
To calculate depreciation expense using the diminishing-balance method, we need to determine the depreciation rate. Since the question states that the depreciation rate is equal to one time the straight-line rate, we can find the straight-line rate by dividing the difference between the cost and the residual value by the useful life in years. In this case, the straight-line rate would be ($81,600 - $8,540) / 4 = $18,515 per year.
To calculate the depreciation expense for 2021, we multiply the beginning book value of the truck (which is the cost) by the depreciation rate. The depreciation expense for 2021 would be $81,600 * $18,515 = $15,120.
To calculate the depreciation expense for 2022, we first need to find the book value at the beginning of the year. Since the company has a December 31 year end, we calculate the book value as the cost minus the accumulated depreciation up until the end of the previous year. The accumulated depreciation for 2021 would be $15,120. Then, we can calculate the depreciation expense for 2022 by multiplying the beginning book value by the depreciation rate. The depreciation expense for 2022 would be ($81,600 - $15,120) * $18,515 = $12,259.