There are 16 trains arriving on time at a railway station on January 1, and 4 trains are delayed. What is the punctuality rate of the trains on that day?
某火车站1月1日这一天正点到站的火车有16列，另外有4列误点，火车当天的正点率是多少？
<gadget id="calculator">16 + 4</gadget>
<output>20</output>

<gadget id="calculator">16 / 20</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">100 / 100</gadget>
<output>1</output>

<gadget id="calculator">(4/5) * 1</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>