Terminology misuse.
Xenos has 48 ALUs, each ALU can do 2 math ops per clock cycle, but these 2 ops work on different data types.
The first operation works on 4-way vectors, the second one works on scalar values, so we can say Xenos can do 48*2*500*10^6 = 48 bilions shading ops per second.
But this is a meaningless number cause the term 'shading operation' is not well defined.
As you can see is used to label operations on different mathematical entities/objects, so it's like adding apples with oranges, it breaks basic algebra
A much better metric that one can use to understand how much work Xenos ALUs can do is based around the number of floating point operations per clock cycle ALUs can execute.
A much better metric that one can use to understand how much work Xenos ALUs can do is based around the number of floating point operations per clock cycle ALUs can execute.