I don't know the Python off the top of my head but it's straightforward in GREL
If we assume that the value datatype is already a number:
ceil(value/100.0)
or if it's a string:
ceil(value.toNumber()/100.0)
Note that I'm dividing by 100.0 (with the decimal) deliberately - this forces a float (a number with a decimal for our purposes) as the result (because of the way OpenRefine handles numbers, you can sometimes get an integer if you simply divide by 100 without the decimal point)
Python will also have a ceiling function if you have to do it with Python
Best wishes
Owen