The position vectors of the points P and Q are respectively \(\rm- 2\overline i - 3\overline j + \overline k \) and \(\rm3\overline i + 3\overline j + 2\overline k \) . The ratio in which the point having position vector \(\rm\frac{{ - 9}}{2}\overline i - 6\overline j + \frac{1}{2}\overline k \) divides the line segment joining P and Q is