The hero team conducts field military training. It walks 20km in sunny days, 12km in rainy days, and a total of 84km in 5 days. How many days are sunny days?
英雄小分队进行野外军训，晴天行20km，雨天行12km，5天共行84km，则有多少天是晴天．
<gadget id="calculator">5 * 12</gadget>
<output>60</output>

<gadget id="calculator">84 - 60</gadget>
<output>24</output>

<gadget id="calculator">20 - 12</gadget>
<output>8</output>

<gadget id="calculator">24 / 8</gadget>
<output>3</output>

<result>3</result>