Interest and savings
Put money in and watch it grow. With compound interest you also earn interest on the interest — the table shows it year by year.
Your numbers
Answer
Final amount
13,439.16DKK
Total interest
3,439.16DKK
Doubled after
23.4 year
How to work it out
- 1K = K₀ · (1 + r)ⁿ
- 2K = 10,000 · (1 + 0.03)^10
- 3K = 10,000 · 1.343916 = 13,439.16
The formula
K = K₀ · (1 + r)ⁿ
Compound interest: the interest is added every year, and the next year you also earn interest on the interest.
K = K₀ · (1 + r · n)
Simple interest: you only earn interest on the starting amount.
r is written as a decimal in the formula: 3 % = 0.03.
Year by year
| Year | Interest that year | Amount |
|---|---|---|
| 0 | — | 10,000 |
| 1 | 300 | 10,300 |
| 2 | 309 | 10,609 |
| 3 | 318.27 | 10,927.27 |
| 4 | 327.82 | 11,255.09 |
| 5 | 337.65 | 11,592.74 |
| 6 | 347.78 | 11,940.52 |
| 7 | 358.22 | 12,298.74 |
| 8 | 368.96 | 12,667.7 |
| 9 | 380.03 | 13,047.73 |
| 10 | 391.43 | 13,439.16 |