A project can be completed by team A alone in 20 days and team B alone in 30 days. Now the two teams are doing it together, during which Team A rested for 3 days and Team B rested for several days. It took 16 days from start to finish, how many days did Team B rest?
一项工程，甲队单独做20天完成，乙队单独做30天完成．现在他们两队一起做，其间甲队休息了3天乙队休息了若干天．从开始到完成共用了16天，问乙队休息了多少天？
<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 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(1/30) * 16</gadget>
<output>8/15 = around 0.533333</output>

<gadget id="calculator">(8/15) - 1</gadget>
<output>-7/15 = around -0.466667</output>

<gadget id="calculator">(13/20) + (-7/15)</gadget>
<output>11/60 = around 0.183333</output>

<gadget id="calculator">(11/60) / (1/30)</gadget>
<output>11/2 = around 5.5</output>

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