SSC GD Constable 15 Feb 2019 Shift 3 Paper

The average weight of all the students in a class was 45.5 kg. Later on 5 students weighing 44.6 kg 43.4 kg, 44 kg, 45.5 kg and 43.5 kg leave the class. As a result, the average weight of the remaining students increases by 500 g. What was the number of students in the class, initially?