It takes (1/20) hours to cut a piece of wood into 3 sections. If the time for each cut is the same, how many hours will it take to cut it into 9 sections?
一根木料把它截成3段，需(1/20)小时，如果每截一次所用的时间相同，截成9段共用多少小时．
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">(1/20) / 2</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">9 - 1</gadget>
<output>8</output>

<gadget id="calculator">(1/40) * 8</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>