In a hostel, 75 students had food provision for 24 days. If 15 students leave the hostel, for how many days would the food provision last?

More the number of men, lesser the days to feed them by given food. So, it is an inverse proportion.

Let the required days be x.

⇒ 75 × 24 = 60 × x

⇒ x = = 30 days