The three astronauts are going to complete a space science experiment on Tiangong-1. It is known that after Jing Haipeng completed it for 15 hours (1/4), Liu Wang joins in and the two cooperate to complete it again (1/4). At this time, Liu Yang also joined the three to do it together, and finally the three completed the experiment together. It is known that the working efficiency ratio between Liu Wang and Liu Yang is 3:5, and the working time ratio between Liu Wang and Liu Yang is 2:1 during the completion of the experiment. How many hours did it take to complete this scientific experiment on Tiangong-1?
三名宇航员要完成天宫一号上一项太空科学实验，已知景海鹏做15小时完成(1/4)以后，刘旺加入一起做，两人又合作完成了(1/4)，这时刘洋也加入三人一起做，最后三人合做完成了实验．已知刘旺与刘洋工作效率比为3：5，完成实验工作过程中，刘旺和刘洋工作时间的比为2：1，求在天宫一号上的这项科学实验完成共用多少小时？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/4) / 15</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">3 / 120</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">(1/60) + (1/40)</gadget>
<output>1/24 = around 0.041667</output>

<gadget id="calculator">(1/4) / (1/24)</gadget>
<output>6</output>

<gadget id="calculator">1 - (1/4) - (1/4)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">5 / 120</gadget>
<output>1/24 = around 0.041667</output>

<gadget id="calculator">(1/60) + (1/40) + (1/24)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/2) / (1/12)</gadget>
<output>6</output>

<gadget id="calculator">15 + 6 + 6</gadget>
<output>27</output>

<result>27</result>