2 masters and 4 apprentices can complete a batch of parts in one day (3/10), 6 masters and 16 apprentices can complete this batch of parts on the first day, if the master completes all the parts in one day , how many masters are needed?
2个师傅和4个徒弟一天可以做完一批零件的(3/10)，6个师傅和16个徒弟第一天就能把这批零件做完，若这批零件全部由师傅一天做完，则需要师傅多少人？
<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(3/10) * 3</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">1 - (9/10)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">4 * 3</gadget>
<output>12</output>

<gadget id="calculator">16 - 12</gadget>
<output>4</output>

<gadget id="calculator">(1/10) / 4</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">(1/40) * 4</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(3/10) - (1/10)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) / 2</gadget>
<output>1/10 = around 0.1</output>

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

<result>10</result>