This is a catch-up problem. After 1 km left the school gate, we can know from the drawing that from the time when the physical education committee member left until he caught up with other students (assuming it was him, it was convenient, and we also supported women's rights), during this period, he walked more 1*2=2 km, and walked more than the class every hour 1 km, so he had to. He walked for two hours, and it took 0. 1 hour to get the battery. No matter whether you take the battery or walk, the class is forward, so the class is forward (2+0. 1)*4=8.4 kilometers, so the total distance is: 8.4+ 1+ 1 =.

Namely:1+[(1* 2)/(5-4)+0.1] * 4+1=10.4km.