Are calculators ever wrong? - Answers

Yes, except when calculating the simplest operations they use approximation methods that only produce "good enough" answers not right answers. Also irrational, most rational, and numbers needing higher precision than the calculator has will have rounding errors.There are many other sources of error in calculator results and understanding their sources will help avoid getting meaningless results, but many calculator manuals do not cover these issues (a full understanding often requires knowledge of some very difficult mathematical theory).