A and B set off from A and B at the same time, and meet at the midpoint 6 hours later; if A walks 4 kilometers more per hour and B starts 1 hour earlier, they still meet at the midpoint. So how many kilometers are the distance between the two places?
甲、乙两人分别从A、B两地同时出发，6小时后在中点相遇；若甲每小时多走4千米，乙提前1小时出发，则仍在中点相遇．那么两地相距多少千米？
<gadget id="calculator">4 * 6</gadget>
<output>24</output>

<gadget id="calculator">24 - 4</gadget>
<output>20</output>

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

<gadget id="calculator">(1/6) * 6</gadget>
<output>1</output>

<gadget id="calculator">(1/6) - 1</gadget>
<output>-5/6 = around -0.833333</output>

<gadget id="calculator">1 + (-5/6)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">20 / (1/6)</gadget>
<output>120</output>

<gadget id="calculator">120 * 2</gadget>
<output>240</output>

<result>240</result>