As shown in the figure, a light uniform rod PQ of length 150 cm is suspended from the ceiling horizontally using two metal wires A and B tied to the ends of the rod. The ratios of the radii and the Young's moduli of the materials of the two wires A and B are respectively 2: 3 and 3: 2 . The position at which a weight should be suspended from the rod such that the elongations of the two wires become equal is