Process a batch of parts, master Huang (1/4) day to complete, Hong master (1/3) day to complete. The processing task can be completed within a few days of cooperation between the two.
加工一批零件，黄师傅(1/4)天完成，洪师傅(1/3)天完成．两人合作多少天就可以完成加工任务．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / (1/4)</gadget>
<output>4</output>

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

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

<gadget id="calculator">4 + 3</gadget>
<output>7</output>

<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<result>1/7 = around 0.142857</result>