There were 45 students in a hostel, if the numbers of students increased by 7, the expenses of the mess were increased by Rs. 39 per day while the average expenditure per head diminished by Re.1. What is the original expenditure of the mess? Pick one:
A) 575
B) 585
C) 595
D) 625
E) 555
Explanation:   Let the original expenditure be Rs.x   Original average expenditure = X/45   New average expenditure = (x+39)/52   So (x/45) – ((x+39) / 52) = 1 so x = 585   so, original expenditure is Rs 585   Answer: 585
<result>B</result>
There were 45 students in a hostel, if the numbers of students increased by 7, the expenses of the mess were increased by Rs. 39 per day while the average expenditure per head diminished by Re.1. What is the original expenditure of the mess?