If I were taking a trip and it took me three hours to get there and 5 hours to get back, what would be speed have been on the way there if I traveled at 16k/h?
speed is distance traveled over unit time:
v = d/t
rearranging,
d = vt
let v = speed going there (forth)
since in the problem, you traveled the same distance,
d,forth = d,back
3v = 5(16)
3v = 80
v = 80/3 or 26.67 k/h