A car has traveled 40% of the journey from place A to place B, and if it travels another 20 kilometers, it will travel exactly half of the journey. How many kilometers are there between A and B?
一辆汽车从甲地开往乙地，已经行了全程的40%，再行20千米，就正好行了全程的一半．甲乙两地相距多少千米？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

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

<gadget id="calculator">20 / (1/10)</gadget>
<output>200</output>

<result>200</result>