A truck has traveled the entire distance (3/5) from point A to point B, which is exactly 40 kilometers away from the midpoint. How many kilometers are there between A and B?
一辆货车从甲地开往乙地，已经行了全程的(3/5)，正好离中点40千米．甲乙两地相距多少千米？
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 / 2</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">40 / (1/10)</gadget>
<output>400</output>

<result>400</result>