In June, there are 18 days in a city where the air quality is above excellent, accounting for the total number of days in June.
某市六月份空气质量达到优良以上的有18天，占六月份总天数的多少．
<gadget id="calculator">18 / 30</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>