In school assembly, students of a class are standing in a line. Ruhi is 19th from both ends. How many students are present in that class?

If Ruhi is 19th from both ends, we count 18 students before her, Ruhi herself, and 18 students after her. Total = 18 + 1 + 18 = 37 students. The formula is: Total = (position from front) + (position from back) − 1 = 19 + 19 − 1 = 37.