Xiao Zhang, Xiao Wang, and Xiao Li start from the same place by the lake at the same time and walk around the lake. Xiao Zhang's speed is 5.4 km/h, and Xiao Wang's speed is 4.2 km/h. They both walk in the same direction, and Xiao Li walks in the opposite direction with them. Half an hour later, Xiao Li and Xiao Zhang meet, and after 5 Minutes later, Xiao Li and Xiao Wang met. So how many kilometers is the journey around the lake?
小张、小王、小李同时从湖边同一地点出发，绕湖行走．小张的速度是5.4千米/小时，小王的速度是4.2千米/小时，他们两人同向行走，小李与他们反向行走，半小时后小李和小张相遇，再经过5分钟，小李与小王相遇．那么绕湖一周的行程是多少千米？
<gadget id="calculator">5.4 / 60</gadget>
<output>0.09</output>

<gadget id="calculator">0.09 * 30</gadget>
<output>2.7</output>

<gadget id="calculator">4.2 / 60</gadget>
<output>0.07</output>

<gadget id="calculator">0.07 * 35</gadget>
<output>2.45</output>

<gadget id="calculator">2.7 - 2.45</gadget>
<output>0.25</output>

<gadget id="calculator">0.25 / 5</gadget>
<output>0.05</output>

<gadget id="calculator">0.05 + 0.09</gadget>
<output>0.14</output>

<gadget id="calculator">0.14 * 30</gadget>
<output>4.2</output>

<result>4.2</result>