The entries in a certain row of Pascal's triangle are \[1, n, \dots, n, 1.\] The average of the entries in this row is 2. Find $n$.
The entries in a certain row of Pascal's triangle ...
The average of the entries in this row is 2. Find n.
The fourth row will do it, 1 3 3 1. The average is 2. n = 3
.