To build a road, (1/6) was repaired in the first 9 days, and then the work efficiency increased (1/5), how many days did it take to repair half of the road?
修一条公路，前9天修了它的(1/6)，之后工作效率提高了(1/5)，这条路修到一半时用了多少天？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/2) - (1/6)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/6) / 9</gadget>
<output>1/54 = around 0.018519</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">(1/54) * (6/5)</gadget>
<output>1/45 = around 0.022222</output>

<gadget id="calculator">(1/3) / (1/45)</gadget>
<output>15</output>

<gadget id="calculator">15 + 9</gadget>
<output>24</output>

<result>24</result>