Car A drives from point A to point B, and car B drives from point B to point A at the same time. When car A travels to the full distance (4/7), the ratio of the distance traveled by car B to the remaining distance is 3:2 , At this time the distance between the two cars is 120 km. Find the distance in kilometers between A and B.
甲车从A地开往B地，乙车同时从B地开往A地，当甲车行到全程的(4/7)时，乙车已行路程与剩下路程的比是3：2，这时两车相距120千米．求A、B两地相距多少千米．
<gadget id="calculator">3 + 2</gadget>
<output>5</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">4 / 7</gadget>
<output>4/7 = around 0.571429</output>

<gadget id="calculator">(4/7) - 1</gadget>
<output>-3/7 = around -0.428571</output>

<gadget id="calculator">(3/5) + (-3/7)</gadget>
<output>6/35 = around 0.171429</output>

<gadget id="calculator">120 / (6/35)</gadget>
<output>700</output>

<result>700</result>