A car drives from place A to place B, and travels the whole distance (2/5), and there is still 15 kilometers away from the midpoint. How many kilometers are there between places A and B?
一辆车从甲地开往乙地，行了全程的(2/5)，离中点还有15千米，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">2 / 5</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">15 / (1/10)</gadget>
<output>150</output>

<result>150</result>