The basket contains N numbered balls $1; 2; ...; N$. From the basket without returns $n<=N$ balls are retrieved. Let S denote the sum of numbers a moat of taken out balls. Find the mathematical expectation E (S) and the variance this Var (S) of this sum.
Solution:
I wanted to clarify, to solve this problem, you need to write a distribution and then start counting and if you need a distribution, then which one?