Q. There were 35 students in a hostel. If the number of students increase by 7, the expenses of the mess increase by Rs 42 per day while the average expenditure per head diminishes by Rs 1. Find the original expenditure of the mess?
Solution / Explanation :
Let the original average expenditure be Rs.x .
Then, 42(x – 1) – 35x = 42
=> 7x = 84
=> x = 12
Therefore original expenditure,
= Rs.(35 * 12)