A train travels from A to B, and when it travels 60% of the journey, it exceeds the midpoint by 500 kilometers. How many kilometers are there between A and B?
一列火车从甲地开往乙地，当行了全程的60%时，超过中点500千米．甲乙两地相距多少千米？
<gadget id="calculator">60 / 100</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(3/5) - (1/2)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">500 / (1/10)</gadget>
<output>5_000</output>

<result>5_000</result>