A section of road is divided into three sections: uphill, flat, and downhill. The ratio of each section is 1:2:3, and the ratio of the time someone spends on each section is 4:5:6. It is known that he travels 3 kilometers per hour uphill, and the total length of the journey is 24 kilometers. How many hours does it take to complete the journey?
一段路分上坡、平路、下坡三段，各段路程的比是1：2：3，某人在各段上所用时间的比是4：5：6．已知他上坡每小时行3千米，路程全长24千米，行完全程共用多少小时？
<gadget id="calculator">1 + 2 + 3</gadget>
<output>6</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/6) / 3 / 4</gadget>
<output>1/72 = around 0.013889</output>

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

<gadget id="calculator">24 * (1/72) * 15</gadget>
<output>5</output>

<result>5</result>