Simple interest earned
A saver is told the interest they would earn: principal held for years at a whole-percent annual rate, with no compounding.
- Pay the simple rate: principal × rate × years, in minor units.
- The product is divided by 100 for the percent, rounding down.
- A zero rate, zero principal, or zero years all pay nothing.
simple_interest(principal: int, rate_percent: int, years: int) → int
Where you start
def simple_interest(principal: int, rate_percent: int, years: int) -> int:
Worked examples
| Call | Result |
|---|---|
simple_interest(1000, 5, 2) | 100 |
simple_interest(10000, 10, 5) | 5000 |
simple_interest(1234, 5, 3) | 185 |
simple_interest(2500, 0, 10) | 0 |
Hint
Multiply all three, divide and round down.
Reference solution in Python
def simple_interest(principal: int, rate_percent: int, years: int) -> int:
return principal * rate_percent * years // 100