Apologies but I am having difficulty understanding how to convert a simple expression to a summation.
I have three parameters:
x = final rating
y = major criteria
z = minor criteria
The final rating is the sum of the major criteria (which is multipled by 2) and the minor criteria. So something like: $x = 2y + z$
But there can be multiple $y$ and $z$. For example, if I had 2 major criteria and 3 minor criteria, the expression would look like: $x = 2y{_1}+2y{_2}+z{_1}+z{_2}+z{_3}$
So would the summation look like this?
$$x = \sum_{n=0}{2y_n + z_n}$$