Thanks Hermione. (I did consider placing the topic in this subboard but I thought for sure it would get moved…D’oh!).
That calculator is a Godsend.

As it turns out, there are several alternative renderings, three of which are:

— 1/4 + 1/50 + 1/100;

— 1/5 + 1/25 + 1/30 + 1/150 (all denominators are multiples of 5); and,

— 1/4 + 1/44 + 1/198 + 1/450.

Your time and help is greatly appreciated.