A project is completed in 20 days by the cooperation of teams A and B. After 8 days of joint work, A leaves and B continues to work on it for 18 days. If this project is done by B alone, how many days can it be completed?
一项工程，甲乙队合作20天完成，共同做了8天以后，甲离开了，由乙继续做了18天才完成，如果这项工程由乙队独做，几天可以完成？
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(1/20) * 8</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(3/5) / 18</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">1 / (1/30)</gadget>
<output>30</output>

<result>30</result>