19.55 rounded to the nearest tenth would be 20, the reason for this is because:
1|9| .55 - As you are rounding to the nearest ten, you would look at the value in this location, if it is 5 or higher, then it has to be 20, however if this value is 4 or lower, the nearest tenth would be 10.
It is 232.4 when rounded to the nearest tenth
It is then 20.2 when rounded to the nearest tenth
10.5
33.8
45.1
It is then 52.8 when rounded to the nearest tenth
It is then 56.5 when rounded to the nearest tenth
It is 232.4 when rounded to the nearest tenth
It is then 20.2 when rounded to the nearest tenth
It is 0.8 when rounded to the nearest tenth
4.4
10775.9
2.7
54.4
28.6
965.4
2.1