One piece of work, A alone takes 20 days, B alone takes 30 days, and two people cooperate to complete the work in 16 days. It is known that A has a 3-day break in the middle, and how many days does B take a break?
一件工作，甲独做需20天，乙独做需30天，两人合作16天完工，已知甲中途休息了3天，乙休息了几天？
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">16 - 3</gadget>
<output>13</output>

<gadget id="calculator">(1/20) * 13</gadget>
<output>13/20 = around 0.65</output>

<gadget id="calculator">1 - (13/20)</gadget>
<output>7/20 = around 0.35</output>

<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(7/20) / (1/30)</gadget>
<output>21/2 = around 10.5</output>

<gadget id="calculator">16 - (21/2)</gadget>
<output>11/2 = around 5.5</output>

<result>11/2 = around 5.5</result>