From A to B, A and B need to ride bicycles for 4 hours and 6 hours, respectively. Now A and B start from A and B at the same time and walk toward each other. When they meet, they are 2 kilometers away from the midpoint of A and B. If A After going to B and B to A, turn back immediately, how many kilometers are there between the second meeting place and the first meeting place.
从甲地到乙地，A、B分别需骑车4小时和6小时，现在A、B分别从甲乙两地同时出发，相向而行，相遇时距甲乙两地中点2千米，如果A到乙地与B到A地之后，都立即折回，第二次相遇地点与第一次相遇地点之间有多少千米．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/4) + (1/6)</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">1 / (5/12)</gadget>
<output>12/5 = around 2.4</output>

<gadget id="calculator">(1/4) - (1/6)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">2 / (12/5) / (1/12)</gadget>
<output>10</output>

<gadget id="calculator">2 * 10</gadget>
<output>20</output>

<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 + 2</gadget>
<output>12</output>

<gadget id="calculator">20 - 12</gadget>
<output>8</output>

<result>8</result>