A, B, C, and D all need to travel from A to B, which is 90 kilometers apart. A rides a motorcycle and can only take one person at a time. The motorcycle travels 40 kilometers per hour, and the person travels 4,000 kilometers per hour on foot. M, if four people start from point A at the same time and arrive at point B by using a combination of motorcycles and walking, how long will it take the fastest?
甲、乙、丙、丁四人都要从相距90千米的A地到B，甲骑摩托车，一次只能带一个人，摩托车每小时行40千米，人步行每小时行4千米，如果采用摩托车和步行相结合的办法，4人同时从A地出发，全部到达B地，最快的要多长时间？
<gadget id="calculator">165 / 92</gadget>
<output>165/92 = around 1.793478</output>

<gadget id="calculator">56 / 11</gadget>
<output>56/11 = around 5.090909</output>

<gadget id="calculator">(165/92) * (56/11)</gadget>
<output>210/23 = around 9.130435</output>

<result>210/23 = around 9.130435</result>