There were 35 students in a hostel. If the number of students increases by 7, the expenses of the mess increase by Rs. 42 per day while the average expenditure per head diminishes by Re 1. Find the original expenditure of the mess.
Choose the correct choice from the following options
A) Rs. 480	B) Rs. 520	C) Rs. 420	D) Rs. 460	E) None of these
Let d be the average daily expenditure   Original expenditure = 35 × d   New expenditure = 35 × d + 42   New average expenditure will be :   (35 × d + 42)/42 = d - 1   On solving, we get d = 12   Therefore original expenditure = 35 × 12 = 420   Answer: Rs. 420
<result>C</result>
There were 35 students in a hostel. If the number of students increases by 7, the expenses of the mess increase by Rs. 42 per day while the average expenditure per head diminishes by Re 1. Find the original expenditure of the mess.