The thermal power plant brought a pile of coal and planned to burn 0.5 tons per day, so that the coal can be used up in 12 days. Actually burn 0.3 tons per day, so how many days can it burn?
热电厂运来一堆煤，计划每天烧0.5吨，这样可以烧12天把煤用完．实际每天烧0.3吨，这样可以烧多少天呢？
<gadget id="calculator">12 / 0.3</gadget>
<output>40</output>

<gadget id="calculator">0.5 * 40</gadget>
<output>20</output>

<result>20</result>