section of the journey is divided into three sections: uphill, flat road, and downhill. The ratio of each section is 3:2:4. The ratio of the time Li Ming takes to walk these three sections is 5:4:6. It is known that his uphill speed is 4 kilometers per hour, and the total distance is 36 kilometers. How many hours does it take Li Ming to complete the journey?
一段路程分上坡、平路、下坡三段，各段路程比依次为3：2：4，李明走这三段路所用的时间比依次为5：4：6．已知他上坡的速度是每小时4千米，路程总长36千米，李明走完全程需要多少小时？
<gadget id="calculator">3 + 2 + 4</gadget>
<output>9</output>

<gadget id="calculator">3 / 9</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">5 + 4 + 6</gadget>
<output>15</output>

<gadget id="calculator">5 / 15</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) / 4 / (1/3)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">36 * (1/4)</gadget>
<output>9</output>

<result>9</result>