[Equivalence relation: Suppose Xiaoming buys tickets in A = Suppose Xiaoming buys tickets in B +30 seconds (0.5 minutes)]
(X-4*2)/4=(X-6*2+5*2)/6+0.5
X = 26 [Team AB has 26 people respectively, so the total number of people is ***26*2=52].
Total population =26*2=52 (persons)
A: At the beginning, there were 52 people waiting in line.
Analysis: X-4*2: Because there are 4 people buying and leaving in the A window every minute, there are 8 people in the A team after 2 minutes. Suppose Xiaoming is on the A team.
Buy a ticket. At this time, there are just X-4*2 people in front of him.
X-6*2+5*2: Similarly, after 2 minutes, Team B was reduced by 12; And because the B window increases by 5 people per minute, it is
In these two minutes, 10 people have joined the B window. Reduce 12 people, increase 10 people, and finally reduce 2 people.
If Xiao Ming goes to the queue at this time, there will be (X-6*2+5*2) people in front of him.
(X-4*2)/4: If Xiao Ming is on Team A, then the time required for the person in front of him to buy a ticket.
(X-6*2+5*2)/6: If Xiao Ming is on team B, then the time for the person in front of him to buy tickets.
To sum up, the above equation is obtained.