project can be completed by A alone in 10 days. If A and B work together for 5 days, and the rest of the project can be completed by B alone in 10 days, how many days will it take for B to do this project alone?
一件工程，甲独做10天完成，如果甲乙合做5天后，余下的工程由乙独做10天完成，乙独做这件工程要几天？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/10) * 5</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 - (1/2)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">5 + 10</gadget>
<output>15</output>

<gadget id="calculator">(1/2) / 15</gadget>
<output>1/30 = around 0.033333</output>

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

<result>30</result>