// An interest calculator

// Enter amount of money.
begin = 500;

// Enter the interest rate as percent.
interest = 20;

// Try the calculator.
result = begin;
for (i = 1; i <= 20; i++) {
  result = result * (1 + (interest / 100));
  show("For " + i + " years, it becomes " + Math.floor(result) + " dollars! \n");
}