There is a batch of goods, and (1/5) of it is transported every day, how many days can this batch of goods be shipped.
有一批货物，每天运走它的(1/5)，多少天可以运完这批货物．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

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

<result>5</result>