I'm sure there's a way to simplify this but not seeing it in any of the
previous answers. I have a SUMPRODUCT function where the first factor has a
lot of acceptable conditions, and I want to combine them somehow:

=SUMPRODUCT(--(RangeA="A"),--(RangeB="Baltimore))+SUMPRODUCT(--(RangeA="C"),--(RangeB="Baltimore))+SUMPRODUCT(--(RangeA="G"),--(RangeB="Baltimore)) . . .

The only thing changing is the condition in the first factor. rather than
repeat the whole function and add the results together, ideally I could
recode this mess somehow as "=SUMPRODUCT(--(RangeA=OR("A","C","G", . .
..),--(RangeB="Baltimore")). Any ideas? TIA