The canteen of a certain factory plans to use 9 tons of coal, but actually uses 1.2 tons in 5 days. How many tons of coal will be saved this month?
某厂食堂计划用煤9吨，实际5天用去1.2吨，照这样计算这个月节煤多少吨？
<gadget id="calculator">1.2 / 5</gadget>
<output>0.24</output>

<gadget id="calculator">0.24 * 30</gadget>
<output>7.2</output>

<gadget id="calculator">9 - 7.2</gadget>
<output>1.8</output>

<result>1.8</result>