I don't like calling one interpretation of an ambiguous notation a bug but not the other. Either they are both possible bugs or neither are. The ambiguity com

I don't like calling one interpretation of an ambiguous notation a bug but not the other. Either they are both possible bugs or neither are. The ambiguity comes in when we try to apply rules we learned for encoding (handwritten notation) to another encoding scheme (the calculator). Handwritten math uses positional information to encode order of operations. Calculator math can either try to mimic this (like one Casio did) or ignore this and revert to strict "all multiply and divide operations have equal precedence" (which the other Casio did) Fractions and exponents are other areas where handwritten notation and calculator notation don't overlap very well.