1. **State the problem:** We need to find the depreciation rate given the cost of an asset and the annual depreciation charge using the straight-line method. 2. **Formula used:** The straight-line depreciation rate is calculated as: $$\text{Depreciation Rate} = \frac{\text{Annual Depreciation Charge}}{\text{Cost of Asset}} \times 100\%$$ 3. **Given values:** - Cost of asset = 27000 - Annual depreciation charge = 6750 4. **Calculate the depreciation rate:** $$\text{Depreciation Rate} = \frac{6750}{27000} \times 100\% = 0.25 \times 100\% = 25\%$$ 5. **Interpretation:** This means the asset is depreciated at a rate of 25% per annum using the straight-line method. **Final answer:** 25%