Imagine the coordinates as x and y. So if you go out to 2 on the x axis, and up 0 you have one dot. Now go out 2 on the x axis, and up 5 on the y axis. The two dots when connected are vertical. I believe you are correct.
8.333333
let x=8.33333 and 10x=83.33333
10x-x=83.333-8.333
9x=75
x=75/9
x=25/3
x=8 1/3
Now if you meant:
8.383838 then
100x-x=838.3838-8.3838
99x=830
x=830/99
