I bought this calculator to use on tests and exams where graphing calculators are not permitted. What I didn't realize was that the finicky keys on this calculator would make it a chore to enter something so simple as a three digit number. You may have to press a button two or three times before it even registers on the display. It'll take you twenty seconds or more to simply write out a basic arithmetic problem. Even if you have that kind of patience, you'll really need to keep your eyes glued to the display to make sure you didn't make any errors. Save your money and buy a 4 function calculator.