Solution: When Xiaoming arrived at the 4th floor, it showed that Xiaoming had climbed to the 3rd floor. Xiaojun arrived at the third floor, indicating that Xiaojun climbed the second floor (building); Xiao Ming arrived at 16 floor (building), which means he climbed 15 floor (building); So the speed ratio of Xiao Ming and Xiao Jun is:

3:2= 15:x

x=2* 15/3

X= 10 (architecture)

That is, when Xiao Ming climbs the 15 floor (building), Xiao Jun climbs the 10 floor (building) and Xiao Jun climbs the10+1=1.