```ts
/** a divided by b, rounding the result to 2 decimal places. */
export function safeDivide(a: number, b: number): number {
  if (!Number.isFinite(a) || !Number.isFinite(b)) {
    throw new Error('Both arguments must be finite numbers');
  }
  if (b === 0) {
    throw new Error(' divisor of zero is not allowed');
  }

  return Math.round((a / b) * 100) / 100;
}
```