A garment factory processes a batch of 30,000 sets of children's clothing, and 20 people complete 10,000 sets in 10 days. The rest of the requirements are completed within 10 days. How many more people are needed?
服装厂加工一批30000套的童装，20个人10天完成了10000套，其余的要求在10天内完成，需要增加多少人．
<gadget id="calculator">30_000 - 10_000</gadget>
<output>20_000</output>

<gadget id="calculator">10_000 / 20 / 10</gadget>
<output>50</output>

<gadget id="calculator">20_000 / 50 / 10</gadget>
<output>40</output>

<gadget id="calculator">40 - 20</gadget>
<output>20</output>

<result>20</result>