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 $4/3$. Find $n$.
Average of all entries in any row of Pascal's Triangle = 2^(n)/ (n + 1) where n = 0,1,2,3......
So
2^n / ( n +1) = 4/3
2^n = (4/3) (n + 1)
2^n = (4/3) n + (4/3)
Note that this is true when n = 2
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