It takes 20 days for team A to complete a project alone, and 30 days for team B. After team A works alone for 5 days, team B takes part in the work. How many days will it take to complete the task?
单独完成一项工程，甲队要20天，乙队要30天，甲队先独做5天后，乙队参加了工作，还要多少天完成任务？
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(1/20) * 5</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

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

<gadget id="calculator">(1/20) + (1/30)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(3/4) / (1/12)</gadget>
<output>9</output>

<result>9</result>