The interchange of positions between Tanuja and Anuj allows us to use their new and old positions to deduce the total number of students in the row. Initially, Tanuja is 8th from the left and moves to 16th (Anuj's original place), making her Anuj's mirror in this arrangement. Anuj starts 19th from the right and ends up where Tanuja started, confirming both endpoints of their respective positions.
We apply the formula:
\[
\text{Total Students} = \text{Position from left (post-swap)} + \text{Position from right (original)} - 1 = 16 + 19 - 1 = 34.
\]
This setup confirms the row consists of 34 students in total, leveraging the positional interchange effectively.