def lerp(a: float, b: float, t: float) -> float:
    """
    returns a linear interpolation between a and b at t
    :param a: the first value
    :param b: the second value
    :param t: the interpolation value

    Example:
        >>> lerp(0, 1, 0.5)
        >>> 0.5

    """
    return a + t * (b - a)