The starting price of a taxi in a certain city is 3 yuan (that is, no more than 3 yuan per kilometer). After 1 kilometer, an additional 1.4 yuan will be charged for each additional kilometer; when parking and waiting, an additional 0.1 yuan will be charged per minute. One day Xiao Wang went out by taxi and passed a large shopping mall just as the shopping mall was holding a ten-year store celebration event, and the road was congested. After waiting for a while, Xiao Wang got out of the car and walked through the mall, and took another taxi. Afterwards, I found out that if he immediately changed to another taxi when he encountered a traffic jam, the actual cost would be 0.4 yuan less than the actual cost; but if he did not transfer at that time and waited until the road was cleared, the actual cost would be 4 yuan more than the actual cost. Excuse me, how long did it take from Xiao Wang's traffic jam to the road clearing? (The distance to get off and walk through the mall is ignored)
某市出租车起步价3元(即不超过l公里3元)，1公里以后，每增加l公里，加收1.4元；停车等待时，每分钟加收0.1元．一天小王乘出租车外出，途经一大商场时恰逢该商场举行十年店庆活动，道路发生拥堵．在等候一段时间后，小王下车走过商场，换乘了另外一辆出租车．事后知道，如果当他一遇到堵车时就立即换乘其他出租车的话会比实际花费少0.4元：但如果当时不换乘，停车等候一直到道路疏通，就会比实际花费多4元．请问，从小王堵车开始到道路疏通经过了多长时间？(下车走过商场的路程忽略不计)
<gadget id="calculator">0.4 / 0.1</gadget>
<output>4</output>

<gadget id="calculator">4 / 0.1</gadget>
<output>40</output>

<gadget id="calculator">3 - 1.4</gadget>
<output>1.6</output>

<gadget id="calculator">1.6 / 0.1</gadget>
<output>16</output>

<gadget id="calculator">4 + 40 + 16</gadget>
<output>60</output>

<result>60</result>