Two seconds left

_AK and his friends have just submitted their assignments a few seconds before the deadline and they want to celebrate at the Juice Canteen. They decide to pool in all their cash and order some oreo shakes._ You are given an integer $N$, the number of students, and a list of $n$ integers where $c_i$ is the amount of cash the $i$-th student has. Find the average amount that each student can pla