Thank you for answering.
What I really was after though, was the speed at which the calculator reacts to button presses. I hate it when I do lengthy calculations and the FX-85ES fails to register every character I press because it's so slow. Can you say anything about this?
Thank you, that was just the piece of information I was looking for. So the FX-991ES Plus should be reasonably fast then. Do you know how its speed compares to for example Texas's TI-30XS MultiView? I've gotten used to the texbook like display mode, but I don't want to buy another calculator that can't keep up with my typing.
EDIT2: As @simpatico pointed out, this method will not work for numbers that are out of calculator's precision. If you want to compute say 200^5 mod 391 then some tricks from algebra are needed. For example, using rule(A * B) mod C = ((A mod C) * B) mod C we can write:
To do this process on a simple calculator do the following:Take the dividend (7) and divide by the divisor (3), note the answer and discard all the decimals -> example 7/3 = 2.3333333, only worry about the 2. Now multiply this number by the divisor (3) and subtract the resulting number from the original dividend.