Traveling for a distance, A’s travel time is B’s (2/5), then B’s speed is A’s ((())/(())).
行驶一段路程，甲行驶的时间是乙的(2/5)，那么乙的速度是甲的((())/(()))．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 5 / (1/2)</gadget>
<output>2/5 = around 0.4</output>

<result>2/5 = around 0.4</result>