Wuhan Metro No. 2 will be opened in 2012, and the workers are intensely working on the construction. If 8 workers can be transferred, it can be completed in 10 days. If 3 workers can be transferred, it will take 20 days to complete. Only 2 people can be transferred now, so how many days will it take to complete this project?
2012年武汉地铁2号将开通，工人正在紧张的进行施工，如果能调来8个工人，10天就能完成，如果能调来3个人，就要20天才能完成．现在只能调来2个人，那么完成这项工程需要几天？
<gadget id="calculator">8 * 10</gadget>
<output>80</output>

<gadget id="calculator">3 * 20</gadget>
<output>60</output>

<gadget id="calculator">80 - 60</gadget>
<output>20</output>

<gadget id="calculator">20 + 80</gadget>
<output>100</output>

<gadget id="calculator">20 / 10</gadget>
<output>2</output>

<gadget id="calculator">2 + 2</gadget>
<output>4</output>

<gadget id="calculator">100 / 4</gadget>
<output>25</output>

<result>25</result>