def is_multiple(a: float, b: float, tolerance: float=tolerance) ->bool:
    """
    is_multiple - Check whether a%b is 0 within some tolerance.
    :param a: float The number that may be multiple of b
    :param b: float The number a may be a multiple of
    :param tolerance: float Relative tolerance
    :return bool: True if a is a multiple of b within some tolerance
    """
    min_remainder = min(a % b, b - a % b)
    return min_remainder < tolerance * b
