A and B are walking toward each other from A and B at the same time. When they met, they were 120 meters away from A. After meeting, they continued to move forward and returned immediately after reaching the destination. They met again at a distance of 150 meters from A. How far is the distance in meters.
甲、乙两人同时从A、B两地相向而行，相遇时距A地120米，相遇后，他们继续前进，到达目的地后立即返回，在距A地150米处再次相遇，AB两地的距离是多少米．
<gadget id="calculator">120 * 3</gadget>
<output>360</output>

<gadget id="calculator">360 + 150</gadget>
<output>510</output>

<gadget id="calculator">510 / 2</gadget>
<output>255</output>

<result>255</result>