Calculate the interest in a simple way by defining specific principal, interest rate, and period.
| Principal amount | Interest rate | Period | Interest amount | Total amount |
|---|---|---|---|---|
| $1000 | 5% per year | 10 years | $500 | $1500 |
| $5000 | 10% per year | 3 months | $125 | $5125 |
| $50000 | 3% per year | 15 years | $22500 | $72500 |