I've dug my calculator out (original battery since 2008) and I can type A B C D E F M X and Y on it. Maybe they were setting people up for a hardcore version of Countdown.
When I did higher maths the school sold the calculators we needed but I didn't get one from there (for some reason I think an auntie bought it, but anyway), I thought it was the same as the others, looked the same, but it had a bunch more buttons on it, including bring able to convert 44 different measurements to something else. I mind one time in a class we had to follow all these instructions to convert something from some measurement to something else, then I just press two buttons on my calculator and did it automatically. Further proof that maths is a complete waste of time.