A factory plans to make 120 tons of steel in 15 days. In fact, 2 tons more steel is made every day than the original plan. How many days did it actually take to complete the original production task?
某工厂计划15天炼钢120吨．实际每天比原计划多炼钢2吨，要完成原定生产任务实际用了多少天？
<gadget id="calculator">120 / 15</gadget>
<output>8</output>

<gadget id="calculator">8 + 2</gadget>
<output>10</output>

<gadget id="calculator">120 / 10</gadget>
<output>12</output>

<result>12</result>