To build a road, it is planned to build 30 meters per day and it can be completed in 12 days. Actually repair 6 meters more every day, how many days can it be completed in advance?
修一条路，计划每天修30米12天可以修完．实际每天多修6米，可以提前几天修完？
<gadget id="calculator">30 + 6</gadget>
<output>36</output>

<gadget id="calculator">12 / 36</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">30 * (1/3)</gadget>
<output>10</output>

<gadget id="calculator">12 - 10</gadget>
<output>2</output>

<result>2</result>