Since, each student requires 9m2 of floor and given the no. of students is 50.
So the total area of the room is 9m2X50=450m2
Given the length of the room is 25m, so the Breadth is =450/25=18m
SInce, each student requires 108m3 of space , so total volume of the room is 108X50=5400m3
we know that : Volume=Area X h
⇒5400=450Xh
⇒h=5400/450= 12m