Given :
A hostel of 500 boys has provisions for 4 days.
To Find :
If the provisions were continued for 20 days, how many students have gone out of the hostel.
Solution :
Let, number of students left after 20 days are x.
Now, provisions are given by :
Also, provisions remains same.
So, initial provision = final provision
Therefore, 100 students have gone out of the hostel.
Hence, this is the required solution.