Two people, A and B, are walking toward each other from A and B at the same time, and B's speed is (2/3) of A's speed. return. It is known that the place where the two met for the second time is 20 kilometers away from the place where they met for the first time, so how many kilometers are the distance between A and B?
甲、乙二人分别从A，B两地同时相向而行，乙的速度是甲的速度的(2/3)，二人相遇后继续行进，甲到B地、乙到A地后都立即返回．已知二人第二次相遇的地点距第一次相遇的地点是20千米，那么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">(3/5) * 3</gadget>
<output>9/5 = around 1.8</output>

<gadget id="calculator">2 - (9/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(3/5) - (1/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">20 / (2/5)</gadget>
<output>50</output>

<result>50</result>