There were 35 students in a hostel. Due to the admission of 7 new students, the expenses of mess were increased by 42 per day while the average expenditure per head diminished by 1. What was the original expenditure of the mess?
Answers:
A) 400 B) 420 C) 445 D) 465 E) None of the above
Let the original average expenditure be `x.   Then,   42(x – 1) – 35x = 42 ⇔ 7x = 84 ⇒ x = 12.   ∴ Original expenditure = (35 × 12)= 420.   Answer 420
<result>B</result>
There were 35 students in a hostel. Due to the admission of 7 new students, the expenses of mess were increased by 42 per day while the average expenditure per head diminished by 1. What was the original expenditure of the mess?