The cement factory produces a batch of cement. The original plan is to produce 2.4 tons per day, and it will be completed in 30 days. The actual production will be 0.8 tons more per day. How many days will it actually take? (Solve with ratio)
水泥厂生产一批水泥，原计划每天生产2.4吨，30天完成，实际每天多生产0.8吨，实际用多少天完成？(用比例解)
<gadget id="calculator">2.4 * 30</gadget>
<output>72</output>

<gadget id="calculator">2.4 + 0.8</gadget>
<output>3.2</output>

<gadget id="calculator">72 / 3.2</gadget>
<output>22.5</output>

<result>22.5</result>