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A laptop depreciated in value by 20% per annum. Three years after it was purchased, it had depreciated to a value of $2048, using the declining balance method.
What was the purchase price of the laptop? (2 marks) --- 4 WORK AREA LINES (style=lined) ---
`$4000`
`S = V_0 (1 – r)^n`
| `2048` | `= V_0 (1-0.20)^3` |
| `2048` | `= V_0 (0.80)^3` |
| `V_0` | `= 2048 / 0.512` |
| `= 4000` |
`:.\ text(The purchase price) = $4000`
A plasma TV depreciated in value by 15% per annum. Two years after it was purchased it had depreciated to a value of $2023, using the declining balance method.
What was the purchase price of the plasma TV? (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
`$2800`
`S = V_0 (1-r)^n`
| `2023` | `= V_0 (1-0.15)^2` |
| `2023` | `= V_0 (0.85)^2` |
| `V_0` | `= 2023/0.85^2` |
| `= 2800` |
`:.\ text(The purchase price) = $2800`