Question

a hostel mess has provision for 200 student for 30 days. If 100 student join the hostel, how long will be the provision last date

Answer 1

200x30=6000
6000÷100=60

Answer 2

let the provision day to be last now x
students at beginning 200
and provision 30 days
but 100 students join so obviously provision decrease so its inverse variation.
200×30=300×x
6000=300x
x=20