A batch of coal is shipped from Sanjiang Power Plant. If it burns 30 tons per day, this batch of coal can be used for 20 days. If 25 tons of coal are burned every day, how many days can this batch of coal be used?
三江发电厂运来一批煤，如果每天烧30吨，这批煤可以用20天．如果每天烧25吨，这批煤可以用多少天？
<gadget id="calculator">20 / 25</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">30 * (4/5)</gadget>
<output>24</output>

<result>24</result>