The cement plant has 42 tons of coal, which has been burned for 12 days, with an average of 1.6 tons per day. If the remaining coal is burned at 1.5 tons per day, how many days will it last?
水泥厂有煤42吨，已经烧了12天，平均每天烧1.6吨，剩下的烧如果每天烧1.5吨，还可烧多少天？
<gadget id="calculator">12 * 1.6</gadget>
<output>19.2</output>

<gadget id="calculator">42 - 19.2</gadget>
<output>22.8</output>

<gadget id="calculator">22.8 / 1.5</gadget>
<output>15.2</output>

<result>15.2</result>