project, if done by A alone, will be completed in 10 days. It is known that B's work efficiency is 80% of A's. If the project is completed by B alone, how many days will it take to complete?
一项工程，如果由甲独做，10天完成．已知乙的工作效率是甲的80%，如果工程由乙独自完成，需要几天完成？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(1/10) * (4/5)</gadget>
<output>2/25 = around 0.08</output>

<gadget id="calculator">1 / (2/25)</gadget>
<output>25/2 = around 12.5</output>

<result>25/2 = around 12.5</result>