from typing import Counter


def _check_value(x:str) -> float:
    """check value of the elements

    Parameters
    ----------
    x : str

    Examples
    ----------
    >>> _check_value('1.2')
    1.2
    >>> _check_value('1/2')
    0.5

    Returns
    -------
    float
        checked value
    """
    c = Counter(x)
    if '/' in c and c['/'] == 1:
        _a, _b = map(float, x.split('/'))
        return _a / _b
    else:
        return float(x)