def perf_per_dollar(hash_rate: float, cpu_price: float, precision: int) -> float:
    """
    Computes how many hashes per dollar you get. Formula:
    hash_rate / cpu_price

    :param hash_rate: Float. CPU performance in hashes per second.
    :param cpu_price: Float. Current CPU market price.
    :param precision: Int. Precision of computing.
    :return: Float. CPU performance per dollar.
    """
    return round(hash_rate / cpu_price, precision)