def peal_speed_to_blow_interval(peal_minutes: float, num_bells: int) -> float:
    """ Calculate the blow interval from the peal speed, assuming a peal of 5040 changes """
    peal_speed_seconds = peal_minutes * 60
    seconds_per_whole_pull = peal_speed_seconds / 2520  # 2520 whole pulls = 5040 rows
    return seconds_per_whole_pull / (num_bells * 2 + 1)