the question asks to create a pure function that adds any number of arguments.
Is the following acceptable?
sum := Plus[##] &
It does work, but can it be considered a pure function? I felt like it isn't exactly a pure function since it uses the Plus function.
In the examples I've seen for pure functions, the user defines his own custom function instead of using one that is built-in, so I felt like my answer was kind of iffy. Sorry if it seems like a silly question, I am new to Mathematica.
Also, if anyone can provide any other pure functions that have the same effect, I'd greatly appreciate it. Seeing different solutions for one problem helps me learn :)