You can call it whatever you want, as long as it equals 1/2 it’s the same number.
So yes, multiplying by 2/2 to make it more intuitively obvious is perfectly valid and a good way to think about it. Most arithmetic tricks are ultimately multiplying by 1 or adding 0 just to make the problem easier to handle.
Genera are within families, not the other way around. Maybe read a book?
Also: the genus Panthera consists of 5 big cats. The other two big cats that aren’t in Panthera are the cougar, which is also colloquially called a panther, and the cheetah.
So, in fact, “panther” can refer to any big cat other than cheetahs.